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GCSE Digital Technology UNIT 1: THE DIGITAL WORLD Section 2.1.1. - Data Name: Target grade: Teacher: Option: 1 PAGE 1. TYPES OF DATA 2. MEASURING AND STORING DIGITAL DATA Analogue and Digital Data 3-4 Analogue and Digital Devices 5 Binary Digits 7-10 Magnetic Storage 11-12 Optical Storage 13 Solid-State Storage 14 Cloud Storage 15-16 Digital Sound 3. DIGITAL CONVERSION AND PROCESSING Analogue to Digital Conversion 19 Digital to Analogue Conversion 20 Recording and Sampling Digital Sound 21-22 Storing Digital Sound Compression techniques 23 Digital Images Bitmap Images 26-28 Vector Images 29 Storing Digital Images Compression techniques 30 2 1. Types of Data Analogue and Digital Data Analogue Data is used by humans to process information. Humans need analogue data to make sense of the world around us, for example to see and hear things. Everything you see or hear is an uninterrupted flow of data to your senses. Analogue Data: is a continuous range of values   changes smoothly Analogue Data cannot be processed by a computer, It needs to be converted to digital data before a computer can use it. Digital Data is used by computers to process information. Devices such as mobile phones and tablets store photos, music, video and text digitally. Digital Data:   is stored as discrete values is made up of Binary Digits (bits) Digital Data cannot be processed by a human. It needs to be converted to analogue data before a human can use it 3 Analogue and Digital Data - Examples Clocks On this analogue clock the second hand moves continuously and smoothly. This digital clock can only show discrete changes in time, at one-second intervals For example: For example: Between 3:07 and 3:08 this clock can display all values of time. Between 3:07 and 3:08 this clock can only display 60 discrete values: 3:0700 3:0701..........................................................3:0758 3:0759 Thermometers This analogue thermometer (the alcohol or mercury thermometer used in science lessons) displays temperature continuously and smoothly This digital thermometer can only display discrete changes in temperature at 0.1⁰c intervals For example: For example: Between 37⁰c and 38⁰c this thermometer can display all values of temperature Between 37⁰c and 38⁰c this thermometer can only display 10 discrete values: 37.0⁰c 37.1⁰c ............................................ 37.8⁰c 37.9⁰c 4 Analogue and Digital Devices Examples of other analogue devices Weighing Scales Cassette Tape Guitar Film Camera Examples of other digital devices Digital Camera Tablet Smart Phone VR Headset 5 Analogue and Digital Devices - Revision Activities 1. Name two analogue devices (3) ................................................................... ................................................................... ................................................................... 2. Name three digital devices (3) ................................................................... ................................................................... ................................................................... 3. Describe the difference between analogue and digital data (2) ............................................................................................................................................................................................................................ ............................................................................................................................................................................................................................ ............................................................................................................................................................................................................................ ............................................................................................................................................................................................................................ 4. Match up the following facts depending on whether they apply to analogue or digital devices. An example has been done for you (8) Is processed by humans Is made up of binary digits Is stored as discrete values Is a continuously range of values ANALOGUE Changes smoothly Cannot be processed by humans DIGITAL Is processed by computers Is used by devices such as mobile phones Cannot be processed by a computer 5. What needs to happen to analogue data before it can be processed by a computer (1) ............................................................................................................................................................................................................................ ........................................................................................................................................................................................................................... 6 2. Measuring and Storing Digital Data Digital devices cannot process analogue information, they can only process digital data. Digital data is made up of binary digits. Binary is a number system that only uses two digits: 1 and 0. These are known as bits. Bits are the smallest pieces of data that a computer can process/store. All information that is processed by a computer is in the form of a sequence of 1s and 0s. Therefore, all data that we want a computer to process needs to be converted into binary. 1 binary digit is called A bit 4bits are called a A nibble 8 bits are called A byte 7 When you press a key on a keyboard, an electrical signal is sent through the wire into the computer. One key press sends 1 byte (8 bits) of data n The computer converts this byte of data and displays the key you pressed on the screen. 01101110 Every key on a keyboard has its own binary value. This is known as ASCII code. 01110000 01101111 01110001 Part of the ASCII code table is shown here. 01110010 * * 00100000 Scan the QR code below or follow the link to find out more about the bits, bytes and binary storage tinyurl.com/bitsbytes2020 8 Measuring and Storing Digital Data - Revision Activities (1) 1. Fill in the gaps below (3) A bit is either a ……………..…. or a ……………..…. When 8 bits are stored as a binary number, they are called a ………………….. 2. Complete the table below (6) Measure Name 4 bits …………………………….. …………………………….. bytes 1 kilobyte ……………………………..GB 1TB …………………………….. kilobytes 1MB 1,048,576MB …………………………….. 1,048,576 bytes …………………………….. 3. How many bits are there in a byte (1) ................................................................... 4. How many bits in a nibble (1) ................................................................... 5. Name the coding system used to convert letters pressed on a keyboard into binary (1) ................................................................... 6. Describe two features of digital data (2) ....................................................................................................................................................................................................................... ....................................................................................................................................................................................................................... ....................................................................................................................................................................................................................... 7. Describe two features of analogue data (2) ....................................................................................................................................................................................................................... ....................................................................................................................................................................................................................... ....................................................................................................................................................................................................................... 9 Storage Mediums Digital data is stored using different storage devices known as mediums. Users will choose from different types of storage for different activities. Magnetic Storage Mediums Magnetic storage uses a magnetisable coating. Magnetised dots are made on the surface of the material. These dots are created, read and deleted by very small electric magnets. Examples include:  Computer hard-drives  Digital cassette-tapes Common uses:  Saving work on a computer  Backing up work on a network Amount of storage:  An average desktop PC has a 1TB capacity hard-disk.  Most digital cassette-tapes have a maximum storage of 1TB ADVANTAGES OF MAGNETIC STORAGE DISADVANTAGES OF MAGNETIC STORAGE Large capacity, they can store several terabytes of information Not as portable as other technologies. External hard disks are commonly available, but they need to be treated carefully. Low cost per gigabyte - magnetic tape is the Hard-disks have mechanical moving parts, so are cheapest, but hard disk is very low cost as well. less rugged than other storage types Hard Disk offers high speed data retrieval Data can be lost near strong magnetic fields, such as being too near a music speaker Hard Disk offers random access to data. Magnetic tape is very slow. Magnetic tape can hold its data for up to thirty years in the correct environment. Data isn’t accessed as fast as on solid-state devices 11 Storage Mediums Magnetic Storage Mediums —Computer Hard Drives The hard disk is the main storage device in a computer. It works like a filing cabinet: all of your data files and applications software are stored on it. The hard disk contains a number of metal platters which have been coated with a special magnetic material. The data is stored in this magnetic material. In order to access the data, the platters spin many thousands of times a second and a magnetic read and write head floats just above the surface of the platter. When you hear the term 'hard disk crash', this refers to the read/write head crashing down onto the surface of the hard disk. There is a risk every time this happens that the data stored in the section just where the head crashes might be damaged. That is why it is a bad idea just to switch the computer off at the wall without shutting it down properly. There may even be several hard disks fitted inside some computers . Scan the QR code below or follow the link to find out more about how hard-drives work. Watch the video until 13:40 tinyurl.com/harddrive2020 12 Storage Mediums Optical Storage Optical storage uses a laser to shine and reflect light to read stored data. Examples include:  DVD  Blu-ray  CD Common uses:  Storing music and movies  Copying and sharing music files Amount of storage:  A single-sided DVD can store 4.7GB of data. A double-sided DVD can store 8.5GB of data.  A single-sided Blu-ray disc can store 25GB of data. A double-sided Blu-ray disc can store 50GB  A CD can store around 700MB of data ADVANTAGES OF OPTICAL STORAGE DISADVANTAGES OF OPTICAL STORAGE Cheap if less than 10GB needs to be stored per media item. Not cheap if terabytes need to be stored Very portable compared to hard disk Not as portable as Flash media (like USB) Ideally sized for storing movies and videos. Slow to write (burn) to and much slower data retrieval than a hard disk. They are not affected by magnetic fields. Easily scratched Scan the QR code on the right or follow the link to find out more about blu-ray and other optical storage tinyurl.com/bluray2020 13 Storage Mediums Solid-state Storage Solid-state storage has no moving parts. It holds data using electronic switches. If the switch is open, it represents a '1', since it retains an electric charge. If it is closed, it represents a '0'. It is an electrical form of storage, unlike magnetic or optical media. It is also known as 'Flash memory'. Examples include:  USB  SSD drive  SD cards Common uses:  USBs are used to store and transport computer files  SSD drives are used for storage in computers (instead of magnetic hard-disks)  SD cards are used to store and transfer photos when using a digital camera Amount of storage:  The maximum storage of a USB is 1TB of data. Common USB will store 256TB to 512TB  An SSD drive can store up to 100TB of data  An SD card can store up to 2TB of data ADVANTAGES OF SOLID-STATE STORAGE DISADVANTAGES OF SOLID-STATE STORAGE Faster data retrieval than hard disk as there are no mechanical parts need to be moved to read / write data.. Solid State Drives are expensive compared to a hard disk of similar capacity. Large capacity, especially SSD drives SSDs don’t last as long as hard-disk drives Very tough and rugged as it has no moving parts unlike a hard disk USBs are easily lost or stolen. This has lead to data security concerns. Some companies use encrypted USB sticks Very portable in the form of SD memory cards and USB memory sticks The cost of recovering information from an SSD is higher than from hard-disk drives 14 Storage Mediums Cloud Storage Cloud storage stores data at a remote location online. When files and data are sent to the cloud, they are actually being sent to a server that is connected to the internet. Files can be uploaded to a folder system and downloaded as required. The cloud is also used for internet-based software and apps like Google Classroom and Microsoft Office online. Examples include:  Google Drive  Microsoft OneDrive  Apple iCloud Common uses:  Storing school work files  Backing up a computer hard-drive  Backing up music and photos from a phone Amount of storage:  Most cloud storage will offer around 5-20GB of free storage  You can have as much cloud storage as you like - but the more you store, the more you pay  The amount of data in stored in the cloud is increasingly daily. In 2020 it was estimated that there was over 100,073,741,824GB in cloud storage 15 Storage Mediums Cloud Storage ADVANTAGES OF CLOUD STORAGE DISADVANTAGES OF CLOUD STORAGE Data is safely backed up at a remote location so even if you have a disaster such as a fire there will always be a secure backup of your files The network connection has to be very reliable if the connection is slow or unreliable you might not be able to access your files. Speed of data retrieval will depend on the network connection. You can access your files from anywhere with a network connection, you aren't tied to your machine at home There are concerns about data security. You need to be certain that the company is reputable i.e. that they will perform regular backups of your data and that they have good security in place so that no one can access your data. It usually costs money to store data in the cloud. A company does not have to pay the energy costs Some businesses might give you a small amount of of running a large server. storage space for free but will charge for providing extra space. Data storage is more efficient because you only pay for the exact amount of data you need to store. Scan the QR code below or follow the link to find out more about the durability of some different storage mediums. tinyurl.com/cloudstorage2020 If the data storage company goes out of business then all of the data stored on their servers may be lost (or not available to access) Scan the QR code below or follow the link to find out more about the durability of some different storage mediums. tinyurl.com/compared2020 16 3. Digital Conversion and Processing Digital Sound When musicians create sounds using their voice or a musical instrument they produce analogue data. We have already learned that humans process analogue data and computers process digital data. If a musician wants to record and edit their music on a computer then they will have to convert the data from analogue to digital. ANALOGUE TO DIGITAL CONVERSION Will is a professional musician he wants to record a new song he has written. Then he wants add some effects using his computer. Will sings into a microphone that is connected to his computer. The sound waves that Will produces as he sings are analogue data. Will’s voice is converted into digital data by a device inside the computer called an analogue to digital converter (ADC). The ADC is usually located on a computer’s sound card. Will’s computer can now process his voice recording. He can use apps to add effects like echo or extra bass. 19 Digital Sound When musicians have edit sound on a computer they produce digital data. We have already learned that humans process analogue data and computers process digital data. If a musician wants to be able to listen to their edited music then they will have to convert the data from digital to analogue DIGITAL TO ANALOGUE CONVERSION Will has added an echo effect to his voice using an app on his computer. He now wants to listen back to his song. Will’s voice is converted into analogue data by a device inside the computer called an digital to analogue convertor (DAC) The DAC is usually located on a computer’s sound card. Will can now listen to his voice using the headphones he has connected to his computer. ANALOGUE TO DIGITAL CONVERSION DIGITAL TO ANALOGUE CONVERSION 20 Recording and Sampling Digital Sound Analogue sound can be represented as a sound wave. This sound wave lasts for 10 seconds When a music is recorded onto a computer a process called sampling takes place. In this example, the computer takes one sample per second. Most audio is recorded at over 40,000 samples per second Any sound that takes place between samples is not recorded. This means that the sound loses quality as data has been lost between the time samples. The way to increase the quality and store the sound at a quality closer to the original, is to have more time samples that are closer together. The higher the sampling rate and the bit depth, the better the quality of the recording. 21 Digital Sound SAMPLING RATE BIT DEPTH The amount of samples taken per second is called the sample rate. Bit depth is the number of bits available for each sample. The higher the bit depth, the higher the quality of the sound. The sample rate is measured in Hertz (Hz). SPOTIFY CD Sampling Rate: 48,000Hz Sampling Rate: 44,000Hz Bit Depth: 24 bit Bit Depth: 16bit It is possible to change the sample rate and bit depth that your computer plays through your speakers or headphones. Scan the QR code below or follow the link to find out more about sound recording and sound quality tinyurl.com/soundquality2020 Scan the QR code below or follow the link to find out more about sound sampling tinyurl.com/sampling2020 Scan the QR code below to see how well you can tell the difference in quality of different sound files tinyurl.com/soundquiz2020 22 Storing Digital Sound Digital sound can be stored in many different file types. Choosing between different sound file formats has an effect on the overall sound quality and file size. Uncompressed Digital Sound Uncompressed sound files are high-quality recordings. Uncompressed files normally have a higher sampling rate and bit depth. They are also known as lossless audio. Uncompressed sound files are usually used by professional musicians and in recording studios. Examples of uncompressed sound files: WAV FLAC Average file size of a 3 minute song: 1800MB Average file size of a 3 minute song: 900MB The main advantage of uncompressed digital sound is that they sound almost identical to the original analogue sound recording. A major disadvantage is that the file size of a WAV or FLAC song will be a lot bigger than one that has been saved in a compressed format. Compressed Digital Sound Compressed sound files are lower-quality recordings. Compressed files normally have a lower sampling rate and bit depth. They are also known as lossy audio. Compressed sound files are usually used as music downloads or files from online streaming sites. Examples of compressed sound files: MP3 WMA Average file size of a 3 minute song: 30MB Average file size of a 3 minute song: 30MB The main advantage of compressed digital sound is that because the file size is smaller, a user can download many files onto their device. A disadvantage is that the sound quality is not as good. Many users cannot tell the difference between a compressed and uncompressed sound file. 23 Digital Sound - Revision Activities (1) 1. Name the device that changes a human voice into digital data so it can be processed by a computer (1) …………………………………………………………………………………………………………………………………………………………………… 2. Name the device that changes digital data into sound that can be heard by a human (1) …………………………………………………………………………………………………………………………………………………………………… 3. If sampling takes place at 100Hz, how many samples are being taken per second? (1) …………………………………………………………………………………………………………………………………………………………………… 3. Explain how the sample rate and bit-depth affect the quality of a recording (2) …………………………………………………………………………………………………………………………………………………………………... …………………………………………………………………………………………………………………………………………………………………... …………………………………………………………………………………………………………………………………………………………………… 4. Sample A and Sample B show the same piece of music that has sampled twice at different sample rates. Identify which sample has the higher sample rate. (1) Sample A Sample B ……………………………………………… 5. Users can choose between compressed and uncompressed audio. Explain the difference between these two types of audio. Give one advantage and one disadvantage for each. (6) …………………………………………………………………………………………………………………………………………………………………... …………………………………………………………………………………………………………………………………………………………………... …………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………... …………………………………………………………………………………………………………………………………………………………………... …………………………………………………………………………………………………………………………………………………………………… 24 3. Digital Conversion and Processing Digital Images BITMAP IMAGES To store an image on a computer, the image is broken down into tiny elements called pixels. A pixel (short for picture element) represents one colour. A pixel is the smallest unit of a digital image that can be displayed and edited on a computer screen. Each pixel can have its own individual colour and when pixels are combined together they produce a complete image. Images made up of pixels are known as bitmap images. They are sometimes called raster images. Binary Codes for this image In this black and white picture, each pixel is represented by one bit. 000000 010010 010010 000000 011110 For coloured pictures , each pixel is represented by at least two bits. The number of bits used for each pixel is known as the colour depth Binary Codes for this image 101010101010 100010100010 101110101110 101010101010 100101010110 Resolution Image resolution tells us the quality of an image. The greater the number of pixels used in an image, the higher the resolution and the sharper the image. However, higher resolution images need more storage space. Image resolution is represented by two numbers, such as 1280 × 720. The first number is the number of pixels displayed horizontally and the second number is the number of pixels displayed vertically. The position of a pixel in an image is given using a system similar to (X, Y) coordinates. 26 Digital Images Scan the QR code on the right or follow the link to find out more about storing Bitmap images tinyurl.com/bitmap2020 1. 2. Create your own black and white bitmap image using the grid below. Convert your bitmap image into binary. Use ‘1’ for a black pixel and ‘0’ for a white pixel For example: 01011001 3. How many pixels does your image contain? How many bytes would be needed to store this image (2) ……………………………………………………………………………………………………………………………………………………………... 27 Digital Images Bitmap graphics store details about every individual element (pixel) of the image and since each pixel could have a different colour, this means an image can be very complex. The file size of a bitmap image can be very large because the computer has to store every pixel. Large bitmap images can take a long time to load or to download from the Internet. When you zoom in to or enlarge a bitmap image, pixelation can occur. This means that the pixels become larger on screen and look like a number of small blocks put together. This is the reason why bitmap images are poor quality when they are enlarged too much Bitmap Image Summary What are they made up of? Pixels What can be edited? Individual Pixels What is the file size Large What happens when you enlarge the image? Pixelation it loses quality Do they look like realistic photographs? Yes Common file formats .BMP .JPEG .GIF .PNG 28 Digital Images VECTOR IMAGES Vector images are not made up of a grid of pixels. Instead vector images store information about the objects that make up an image. These objects are things such as lines, curves and shapes and are represented using mathematical calculations. This means it is possible to edit these objects separately, for example by changing the colour, size or the position of the object. Vector images store details about the shape of individual image objects so they require less storage capacity compared to using pixels. This means they can be saved as smaller files and can be easily edited without loss of quality. Since vector-based images are not made up of a grid of pixels, they can be enlarged and not lose image quality. What are they made up of? Objects and mathematical calculations What can be edited? Individual Objects What is the file size Small What happens when you enlarge the image? It is scalable. It does not lose quality Do they look like realistic photographs? No Common file formats .EPS .PDF .SVG 29 Digital Images IMAGE COMPRESSION Large images can take up a lot of storage space and take a long time to download. Using large file sizes can also be expensive. A user storing the images will have to pay for more storage. A user downloading the images will be charged for the increased data they have to use. To reduce the size of an image file we can use image compression. Compression can be lossless or lossy. Lossless compression means that as the file size is compressed, the picture quality remains the same - it does not get worse. Also, the file can be decompressed to its original quality. PNG PNG is a lossless compression type. It is often used where the graphic might be changed by another person or where the image contains layers of graphics that need to be kept separate from each other. It is high quality. Lossy compression permanently removes data. GIF JPEG JPEG is a lossy compression type. JPEGs are often used for digital camera images because hey have a fairly small file size for the quality that it displays. GIF is a lossy compression type. It compresses images to a maximum 8-bit colour depth, so it isn’t suitable for saving as good quality photos. GIF is often used where transparency is needed on the graphic. GIFs can also be used to store simple animated images as moving image files. GIF 30 Digital Images - Revision Activities 1. What is the name of an individual element of a bitmap image(1) …………………………………………………………………………………………………………………………………………………………………… 2. What are bitmap images also known as? (1) …………………………………………………………………………………………………………………………………………………………………… 3. Describe the difference between bitmap and vector images (2) …………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………… 4. Vector images are described as being scalable. Describe what happens when a vector image is enlarged and what happens when a bitmap image is enlarged (2) …………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………… 5. Define the term image resolution. What is the relationship between image resolution and file size? (3) …………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………… 6. Ruby wants to make a simple moving image. Which file type would be the best choice? Explain your answer (2) …………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………… 7. Describe the difference between lossless and lossy compression. (2) …………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………………………………………… 32 Investigation Analysis Design Implementation Maintenance Evaluation Investigation A Systems Analyst investigates the existing system using these methods: Questionnaires Feasibility report Interviews Observing staff The feasibility report will include: The definition of scope of the current system Existing hardware and software Problems with the existing system To show an Does the current Identifying any understanding of hardware/softwar issues with the the requirements e able to cope current system of the new with the and it’s ability to system demands of the meet new new system? requirements. User requirements for the new system The cost and benefits of introducing a new system Wish list of List of solutions to all costs/benefits issues identified noting during fact finding, available and reported by features, required the user hardware or software. Analysis Data Flow Diagrams (DFDs) Maps out the flow of information in a system Decision Tables Data Dictionaries Simplifies decision rules in the form of a user-friendly table Explains what each field in a database means. It can include the data type and possible examples Design The following are included in the system design: • Hardware • Software • Network • Staff issues • Security Procedures Implementation This part of the lifecycle is when the new system is put in place: • Selecting a changover method (pilot/parallel/big-bang) • Installing hardware • Installing software Maintenance This part of the lifecycle is ongoing to support the company with any issues they have: • User Guides • Technical manuals • Error checking Evaluation Evaluating the new system to determine: • How well does the system meet the initial requirements? • What changes need to be made? • How can the system continue to evolve? WJEC GCSE DIGITAL TECHNOLOGY Systems Lifecycle 1. The manager of a local cinema has employed a systems analyst to update the present administration system. Give two methods the analyst might use to collect data about the present system. (2) Method 1: 2. There are a number of stages in the development of a new ICT system. State four tasks carried out during the design stage: Task 1: Task 2: Task 3: Method 2: Task 4: Mr Ratcliff Unit 1 Revision Summer 2023 WJEC GCSE DIGITAL TECHNOLOGY Systems Lifecycle 3. The final stage in the system life cycle process is evaluation. Identifying the good and bad points of the final system is one part of this evaluation stage. Describe two other processes undertaken during the evaluation stage. (2) Process 1: Process 2: Mr Ratcliff 4. The first stage in the creation of a new ICT system is to investigate the existing system. Fill in the table below stating which investigation method would be used in the given circumstances. (3) To find out what a few key people need from the new system To consult a large number of people To see exactly how workers use their current system Unit 1 Revision Summer 2023 Program Software Business Process Management (BPM) Customer Relationship Management Off-the-shelf software that serves a specific purpose. For example, Microsoft Office. Used by companies to develop and automate of processes. Software used by companies to review and analyse customer data Project Management Software Enterprise Resource Planning (ERP) Educational Software Used by companies to plan and implement projects Business software used by companies to manage their daily business Used by companies to teach new content or concepts Resource Management Software Used by companies to manage projects and resources Time Management Software Bespoke Software Used by companies to track how long users spend doing different tasks Software written to achieve a task for an individual or company. It is sometimes called ‘customised software’ or ‘tailored software’.. Productivity Software Used by companies to help users complete their work more efficiently Software written to achieve a task for an individual or company. It is sometimes called ‘customised software’ or ‘tailored software’.. Advantages Disadvantages The software will be able to offer features that are specific to the needs of the company. It takes a long time to develop such a system, between a few months to years because of the specific requirements outlined. The software will work exactly how the company intended it to. It costs a great deal of money to develop such a system, because it’s unique to that company. The software will only have the features that they specifically need in their business. The company may need to employ a team of people such as business analysts, programmers, testers etc WJEC GCSE DIGITAL TECHNOLOGY 2c (i) – Software types and functions Activity : Bespoke Software A local food production company want to upgrade their database so that they store and analyse their customers sales data more efficiently. They are considering purchasing bespoke software to achieve this. Discuss the specific advantages and disadvantages of purchasing bespoke software, giving examples to illustrate your answer (7) Mr Ratcliff Unit 1 Revision Summer 2023 Anti-virus software monitors activity on a computer system for the signs of virus infection. 1) Each virus has its own unique signature that is known to virus protection software and stored in a database. 2) Data stored on a computer system is scanned to see if any of the virus signatures within the database exist on the system. 3) Once a virus has been detected, it notifies the user and it could place the virus in a quarantine folder which will isolate the virus to stop it infecting other parts of the computer. 4) The user can then decide what to do with the virus by going into the quarantine folder. Feature Description Secure banking The software will open the website in a protected browser for additional security. Parental control To control who has access to certain files, programs and devices. Anti-phishing Helps users to identify risks that may present themselves in emails. Virtual private network (VPN) This can be used when users want to use a public network as it will use a different server and protect their own network from data interception and theft. Anti-ransomware A package like this can be useful as it locks areas of the user’s data where important documents and programs are located. Support Useful if software is being updated or customers need help with using the software. Notifications Antivirus companies send regular notifications regarding threats to the system, with a strong recommendation to upgrade the software to solve any issues. 1.The first copy is made and stored. The newest copy of the data is always known as the ‘son’. 2. The next time the data is backed up another copy is made and stored. The previous copy is now referred to as the ‘father’ and the new latest copy is called the ‘son’. 3. The next time the data is backed up and stored, the newest copy is called the ‘son’ the second oldest is referred to as the ‘father’ and the oldest copy is called the ‘grandfather’. 4. For subsequent backups the oldest copy of the data (the ‘grandfather’) is overwritten with the latest data, which becomes known as the ’son’. This way, three backups are stored before the oldest is overwritten. Full backup Incremental backup Advantage: Backups all the data files Advantage: Only the changes are backed up – faster to perform. Disadvantage: It could take a significant time to back up the entire system. Disadvantage: Takes longer to restore all the files because of it needs to restore the full and all the incremental backups. Differential backup Grandfather-Father-Son backup Advantage: Restoring is faster than incremental as only the last full backup and latest differential is needed. Advantage: Create more recovery/restore points (some are off site) while using less storage space. Disadvantage: Restoring is slower than full back up Disadvantage: The restore process will be complex as the last full backup AND the latest differential and will be inefficiently. backup is needed. USB Flash Drive External Hard Drive Portable and lightweight Lower memory capacity Store large amounts of data Good for temporary storage Portable and cheap Solid State Media Cloud Storage Store large amounts of data Stores data on remote servers Robust as they have no moving parts Hosted by an external company Can be very expensive A company must have a plan in case of system failure. The failure could be caused by a powercut or natural disaster The plan details step by step how the company would recover Disaster recovery site Data restoration procedure An alternative location where critical systems and data can be restored if the primary site is damaged or inaccessible. A detailed procedure that outlines how to restore data in case of a data loss event. Recovery Time Objective (RTO) Recovery Point Objective (RPO) The time within which the organisation must restore its systems and data after a data loss event. The point in time to which an organisation is willing to lose data Testing and verification Regular testing and verification can help identify weaknesses in the plan and ensure that the plan will work when needed. Employee training Employees must be trained on the data recovery plan and their respective roles in case of a data loss event. WJEC GCSE DIGITAL TECHNOLOGY Reliability of online sources - You need to understand the definition of each of these keywords: Word Definition Fact Scientifically proven information. Judgement Information that is considered true but may not be completely true. Biased Information believed by a specific group of people who share the same interests. Plagiarism Using someone else’s work and claiming it’s your own. Recognition Crediting the original creator in your own work. Correct Ensuring information is an accurate representation of what happened. Reliable Ensure that information is from a reliable source. Accreditation Supporting information from a reliable source. Solutions to VERIFY infomation: Checking multiple sources To check whether different sources of information state the same information Using trustworthy websites Using well-known and trusted websites such as BBC News, UK Government or WJEC websites Mr Ratcliff Unit 1 Revision Summer 2023 WJEC GCSE DIGITAL TECHNOLOGY User generated sources – e.g. Wikipedia Advantages Mr Ratcliff Disadvantages Wikipedia has articles on almost any topic imaginable, with content available in multiple languages. Because anyone can contribute to Wikipedia, there is no formal system of peer review. This means that the information on Wikipedia may not always be accurate, unbiased, or up-to-date. Anyone can contribute to Wikipedia, which means that articles are constantly being updated and improved. Wikipedia is open to editing by anyone, which means that some individuals may maliciously alter content or add false information. Wikipedia is a free resource, which means that anyone with an internet connection can access it at any time. Some articles may be poorly written, inaccurate, or incomplete. Unit 1 Revision Summer 2023 WJEC GCSE DIGITAL TECHNOLOGY Reliability of online sources Exam style question Sophy has being read lots of positive reviews for a product he wishes to buy online. However, the positive reviews lack detail and there are quite a few negative reviews. Explain why this may cause Sophy to be concerned. Outline two solutions to give Sophy more confidence in her on online research into this product (6 marks) Mr Ratcliff Unit 1 Revision ANSWERS Summer 2023 Pilot A small-scale implementation of a digital system. For example in one part of the office with a set of users, one department of an organisation or one branch. Parallel Big bang Running the old system alongside the new system. The company starts using the new system immediately. Staff from the pilot can help to train other staff. Staff can focus on one area to resolve any problems. For the department doing the pilot, there isn’t a backup system if things go wrong. Slower than other methods.. Users can return to the old system if needed, if there is a problem. The new system is available immediately, if required. The outputs from the old and new systems can be compared to check that the new system is running correctly It is expensive, due to the possible need for additional temporary staff or paying existing staff for their time to operate both systems. Could be cheaper to operate than other methods. The new system is available immediately. This method could be used in situations where failure would not be disastrous. The new system may not work for a while until staff have become used to If the new system fails, the organisation will not have a backup system which could be disastrous. Usability and Risk Pilot Parallel Big bang Usability The new system will run simultaneously, but will only be used by a limited number e.g., one specific department within the company or a designated group.. The new system is available immediately, if required. The old system is switched off, and the new system is used immediately. Risk If something goes wrong with the Users can return to the old system new system, only a small part of the if needed, if there is a problem. organisation is affected. For the department doing the pilot, there isn’t a backup system if things go wrong. If the new system fails, the organisation will not have a backup system which could be disastrous. WJEC GCSE DIGITAL TECHNOLOGY 4b – Implementation of digital systems Impact on staff Identify the impact the following systems would have on staff: (6 marks) • Pilot method • Parallel method • Big bang method Mr Ratcliff Unit 1 Summer 2023 Emails Can send a ‘blanket’ email to every customer Can target customers identified by buying email lists from other companies Advertising through websites Paying another company to advertise your services on their website Social Media Marketing SEO (Search Engine Optimization) SEO is any way of making your company’s search results appear higher in Google search results. Posting on a social media platform to promote a product or service. Can be targeted towards certain groups Best ways are paying Google a subscription or using metadata Influencer Marketing A company gives a new product to a popular person on TikTok or Instagram. The influencer usually gives a positive review, which increases your sales Data Mining Companies analyse a large amount of data to predict trends and to target customers for specific products. Monetizing Content is any way of making money from the content you have created Advantages Disadvantages Can help your brand gain exposure to a larger audience, leading to an increase in brand recognition and awareness. If an influencer is involved in a scandal or controversy, it can negatively impact your brand image if they are associated with your brand. Influencers are often seen as more authentic and trustworthy than traditional advertising because they share their experiences and opinions in a more personal and relatable way. Influencer marketing may not be effective for reaching a broader audience, especially if your brand is not well-known or if your target audience is not active on social media. Can be more cost-effective than traditional advertising because it often involves collaborations or sponsored posts instead of expensive TV ads When working with influencers, you may have less control over the content they create and share Customer segmentation Supermarkets can use data mining techniques to tailor their marketing campaigns and promotions to specific customer groups and offer them more personalized recommendations. Product Recommendation Data mining can be used to identify which products are often purchased together, allowing supermarkets to make recommendations to customers for complementary or related items. Pricing strategies Supermarkets can use data mining to analyse sales and pricing data to identify the most effective pricing strategies for different products and customer segments. Stock control Supermarkets can use data mining to analyse sales data and forecast demand for different products, which can help them optimize inventory levels and reduce waste. WJEC GCSE DIGITAL TECHNOLOGY Marketing Methods Hana would like to raise awareness of her new business, which provides hair and makeup advice for teenagers. Discuss 3 of the best online marketing methods she could use, giving an example how she could utilize each one (6) Mr Ratcliff Unit 1 Revision Summer 2023 Monetizing Content is any way of making money online from the content you have created Affiliate Links You agree to promote other company’s products on your website. Every time someone buys their product, you get a small percentage of the sale. Request Donations Add a donate or support button to content you create on social media. ’ ’ ’ WJEC GCSE DIGITAL TECHNOLOGY Threats to data Using the email shown below, identify the SIX indicators that suggest it could be a phishing email (6). Mr Ratcliff Unit 1 Revision Summer 2023 WJEC GCSE DIGITAL TECHNOLOGY Threats to data A local hospital stores hundreds of patients details on it’s network. The hospital have employed an ethical hacker because they’re concerned about the security of it’s patients sensitive medical data. a) What type of prevention strategy are the hospital using by employing an ethical hacker? (1 mark) b) Identify three errors that the hospital's staff could make, that may endanger the security of the network and outline a procedure that could be put in place to prevent each error. (6 marks) Mr Ratcliff Unit 1 Revision Summer 2023 WJEC GCSE DIGITAL TECHNOLOGY Threats to data A local hospital stores hundreds of patients details on it’s network. c) Using the network threats provided, suggest a suitable strategy that will identify and/or prevent this form of attack. (10 marks) Threat How to identify/prevent vulnerability. Justification Malware Social engineering Brute force attack Data interception Denial of service attack Mr Ratcliff Unit 1 Revision Summer 2023 ’ ’ ’ ’ • • • • • • • ’ WJEC GCSE DIGITAL TECHNOLOGY Digital footprints Active v Passive footprints In the table below, identify if each scenario is an example of an active footprint (with the users knowledge) or passive footprint (without the users knowledge). Active Passive Sending an instant message via Twitter. A web server storing a user’s IP address. Submitting a post on a blog. Sharing a story on Instagram. A user’s browser/search history. Replying to post thread on Facebook Mr Ratcliff Unit 1 Revision Summer 2023 WJEC GCSE DIGITAL TECHNOLOGY Impact of digital footprints Explain how digital footprint would be used for the following purposes Monitoring current employees Monitoring prospective employees (people applying for jobs) Security (the ability to keep the general public safe) Businesses Mr Ratcliff Unit 1 Revision Summer 2023 Lady Ada Lovelace James Gosling Admiral Grace Hopper The first computer programmer, the first person to realise computers could do more than just calculate numbers. The person who developed the Java programming language The person who devised the first commercial electronic computer. Alan Turing Steve Jobs Sir Tim Berners-Lee Developed computational theory on which modern computing is based The person who commoditised computing, and developed smartphones and hand-held devices. Creator of the World Wide Web. Industrial Robots - Used in manufacturing and are programmed to perform specific tasks. For example spraying cars in a factory Welding Painting Assemble Welding car panels together Painting cars Assembling toy components Palleting Packaging Labelling Putting bread on pallets for transport Putting items in boxes ready to be sent out Putting address labels on packages. Autonomous Robots - Have the ability to make their own decisions. For example deciding how to respond to a question in a conversation Robocleaner Robomower Delivery Drones Automatic Guided Vehicles Medical AMRs Move materials in factories and warehouses Send medicine and treatments to hospital wards Effects of robotics on society, culture and the economy Society People that live together in a community. • Loss of lower-skilled, low-paid jobs. The impact on the working environment. Financial/Money related More leisure time as robots take tasks away from people. • Culture Economy • Work of a consistent standard. • • They can work 24/7 • Save money by not having to pay wages to workers • Potential for sensors or software to fail and for the robot to fail or to make unexpected decisions. • Expensive to install and maintain • Creates a number of highly skilled new roles. Lack of human interaction WJEC GCSE DIGITAL TECHNOLOGY 6a – Changing digital technologies Robotics In the table below, list examples of industrial robots and autonomous robots. Industrial robots Mr Ratcliff Autonomous robots Unit 1 Revision Summer 2023 WJEC GCSE DIGITAL TECHNOLOGY 6a – Changing digital technologies Long answer question Explain the impact industrial robots can have on society, culture and the economy. (6 marks) Society Culture Economy Positive: Positive: Positive: Society Culture Economy Negative: Negative: Negative: Mr Ratcliff Unit 1 Revision Summer 2023 Autonomous cars are also known as driverless cars. They are cars that can make some or all decisions themselves without human input. They capture data using RADAR, VIDEO CAMERAS, GPS and SENSORS Advantages • Fewer accidents • Lower insurance costs • Safe speeds could be increased • Reduction in emissions • Improved accessibility for those who can’t drive traditional cars Disadvantages • Possibility the car could be hacked • Potential loss of driving skills • Job losses for taxi and bus drivers • Software malfunctions could cause an accident Social impacts • Bus/Lorry/taxi drivers losing their jobs to autonomous vehicles. • Driverless cars will mean less accidents on the road and lives saved. • The driver won’t need to pay attention and will be able to complete other tasks. • Car sales will go down and the need for car salesmen and mechanics will reduce leading to a loss of employment. Economic impacts • Haulage companies saving money as they won’t have to pay drivers. • Less cars on the road and less accidents will mean more efficient journeys • More jobs created for programmers and people developing the technology. Legal impacts • Who would be at fault if the autonomous vehicle crashed. • Would drivers need insurance. • Data security issues. • New laws needed. Ethical or moral impacts • Should autonomous vehicles be programmed to always protect the occupants in a crash or should they be programmed to take the action that protects the most lives. • Should autonomous vehicles be programmed to consider age, health, human, animal, when making decisions. • Should autonomous vehicles be programmed to consider whether a person crossing the road unlawfully should be put at more risk that the occupants of a car. WJEC GCSE DIGITAL TECHNOLOGY 6b – Changing digital technologies Advantages and disadvantages Exam essay question: Autonomous cars are becoming more widespread on Welsh Roads. Describe what autonomous cars are, making a case for and against their introduction (7) Mr Ratcliff Unit 1 Revision Summer 2023 WJEC GCSE DIGITAL TECHNOLOGY 6b – Changing digital technologies Long answer question Explain the benefits autonomous vehicles can have on society, culture and the economy. (6 marks) Society Culture Economy Keywords: Society – People that live together in a community. Culture – In this context, it’s the impact on the working environment. Economy - The state of a country or region in terms of the production and consumption of goods and services and the supply of money. Mr Ratcliff Unit 1 Revision Summer 2023 Virtual Reality is an application designed to imitate a real-life situation Example uses of VR in education: • Exploring the pyramids in history • Viewing a volcano in geography • Seeing the inside of an atom in science • Viewing different angles of a sports game Advantages Disadvantages • Makes the lesson more immersive • Can distract from the main point of a lesson • Pupils can explore in their own time • Digital divide – not all schools/pupils can afford VR • Many resources online • Privacy concerns • Active rather than passive experience • Health and safety concerns • Boosts creativity • Can make boring topics more interesting WJEC GCSE DIGITAL TECHNOLOGY 6c – Changing digital technologies Identify the advantages and disadvantages to using virtual reality. Use the hints to help you. Hint Advantages Disadvantages Hint How will VR impact social connections and relationships? Affordability and accessibility. People with disabilities VR involves lots of movement – issue? Why do people use VR technology? The time people may spend using VR. Mr Ratcliff Unit 1 Revision Summer 2023 WJEC GCSE DIGITAL TECHNOLOGY 6c – Changing digital technologies Virtual reality In the boxes below, identify which industries are using VR. One has been done for you. Education Mr Ratcliff Unit 1 Revision Summer 2023 WJEC GCSE DIGITAL TECHNOLOGY 6c – Changing digital technologies Explain how virtual reality is being used to improve the following areas. Mr Ratcliff Military: Education: Medicine: Mental health: Unit 1 Revision Summer 2023 Augmented reality is a system used to overlay information about the world around you onto a screen • Navigation systems use AR to superimpose routes over a live view of the road. • During football games, broadcasters use AR to draw lines on the pitch to show and analyse movements and how the goal was scored. • Fighter pilots can see an AR projection of their height, speed and other data on their helmet visor, which means that they do not need to waste focus • Sometimes neurosurgeons use a

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