Computer Components - Computer System Basics

Computer System  What is Computer? --An electronic device designed to accept and store input data, process data and produce appropriate output information under the control of a stored sequence of instructions. -- A device that computes, especially a programmable electr...

Computer System  What is Computer? --An electronic device designed to accept and store input data, process data and produce appropriate output information under the control of a stored sequence of instructions. -- A device that computes, especially a programmable electronic machine that performs high-speed mathematical or logical operations 5 Basic Element that make up a computer 1. Electronic – all computers are powered by electricity 2. Programmable – a computer must be able to follow a set of instructions (called programs) to operate. 5 Basic Element that make up a computer 3. Storage – a computer must be able to store information (like programs and data) to be retrieved at another time. 4. Retrieve – storing is meaningless without the capability to retrieve. 5. Process – a computer must be able to manipulate and transform the information it has stored.  4 Basic Function Input – the procedure of feeding or entering data into a computer. Process – is the operation of manipulating and transforming data into something useful. Output – once data has been processed into information, the computer then must produce and present that information in a form that you can understand. Storage – computers can save data so that it can be used at another time. Classification of Computers According to Purpose General Purpose Computer Special Purpose Computer  General-Purpose Computers are designed to handle a variety of tasks, capable of dealing with variety of different problems, and are able to act in response to program created to meet different needs. It typically comprises certain aspects of speed and efficiency.  Special-Purpose Computer computers designed to perform one specific task. Also known as dedicated computers, because of their limitation to the performance of the specific task at hand. According to Data Handled Analog Computer Digital Computer Hybrid Computer  Analog Computers is a more sophisticated electronic or hydraulic device that is designed to handle input in terms of , voltage levels or hydraulic pressures, rather than numerical data. he inputs are converted into voltages that may be added or multiplied using specially designed circuit elements. It gives approximately result for the user.  Digital Computer It operates counting values that discrete, or separate and distinct. It is used for both business data processing and scientific purposes. Everything that a digital computer does is based on one operation: the ability to determine whether a switch is open or close: on or off (0 or 1).  Hybrid Computer It combines the measuring capabilities of the analog computer and the logical and control capabilities of the digital computer. It offers an efficient and economical method of working out special types of problems in science and various areas of engineering. According to Capacity Microcomputer Minicomputer Mainframe Computer Super Computer Microcomputers is generally synonymous with personal computer (PC), or a computer that depends on a microprocessor. Microcomputers are designed to be used by individuals, whether in the form of PCs, laptops, notebook computers, or even palmtops. Minicomputers a midsized computer or mid-level computer built to perform complex computations while dealing efficiently with a high level of input and output from users connected via terminals. In size and power, minicomputers lie between personal computers and mainframes  Mainframe Computers a very large and expensive computer capable of supporting hundreds, or even thousands of users simultaneously. Mainframes are being used more and more as specialized servers on the World Wide Web, enabling companies to offer secure transactions over the Internet. Workstations Workstations are specialized, single user computers with many of the features of a personal computer but with the processing power of a minicomputer. These are popular among scientists, engineers, graphic artists, animators and programmers. Supercomputers large, extremely fast, and expensive computer. These are used for weather forecasting, large-scale scientific modeling and oil exploration. Supercomputers are relatively rare, used only by large corporation, universities and government agencies that can afford them. Components of the Computer  Components of a Computer earth - globe Hardware (Input & Output Devices earth - globe Input Device earth - globe Output Devices earth - globe System Unit earth - globe Storage Devices  Computer System a complete, working computer. The computer system includes not only the computer, but also any software and peripheral devices that are necessary to make the computer function  Hardware A Hardware is described as any physical component of a computer system that contains a circuit board, Integrated Circuits (ICs), or other electronics. Without any hardware, your computer would not function, and software could not be used. A computer’s hardware is divided into two different components: Input devices and Output devices.  Input Devices Input Devices - is a piece of hardware that sends data to a computer. Most input devices either interact with or control the computer in some way. An input device sends data to the computer.  Keyboard Keyboard – are the most common type of input device. Most English language keyboards use the QWERTY layout for the alphabetic keys, which are surrounded by number, symbol, function, and other key types. By pressing the relevant keys, a user can feed data and instructions to the computer. Keyboard  Mouse Mouse – interacts with a computer through a process known as "point and click." Essentially, when a user moves the mouse on the mouse pad, the pointer moves in a corresponding direction on the computer's monitor screen. It is originally designed by Xerox Mouse Mouse  Trackball Trackball performs the same tasks as the mouse, operates with a rotating metal ball inset in a small, boxlike device. The concept of a computer mouse has its roots in the trackball, a related pointing device invented in 1946 that used a "roller ball" to control a pointer. Trackball  Touchpad Touchpad is a pressure-sensitive pad that is smaller, more accurate, and thinner. It is also known as a trackpad, a touchpad is a common substitute for a computer mouse. It is essentially a specialized surface that can detect the movement of a user's finger to direct a pointer and control a computer. Touchpads were first introduced for laptops in the 1990s, and it's now rare to find a laptop without one. Touchpad  Optical Mark Reader was designed initially to read penciled or graphic information on exam answer sheets. Optical Mark Reader  Scanner Scanner – is an input device that uses optical technology to transfer images (or sometimes text) into a computer, where the signal is converted into a digital image or other file types. The digital image can then be viewed on a monitor screen, saved, edited, emailed, or printed. Scanner Pen scanner  Scanner Applications Another type that is on trend is scanner applications that you can just install in your smartphones for free or for a small amount of money. Adobe Scan runs as an app on your mobile device, whether it is running Android or iOS and uses your camera to catch a copy of a document to convert into a PDF file.  Scanner Applications Abby FineScanner is compatible with Android and iOS, the app lets you scan both printed and handwritten text with your mobile device. FineScanner works with 12 file formats, including DOCX, PDF and TXT. Genius Scan enhances the legibility of documents, ensuring they’re readable, and you can keep your files organized with titles, tags and a search function.  Scanner Applications Scanbot can let you choose from five color modes to make it look perfect. There are also tools to crop and optimize scanned documents, all of which are automatically captured in 200+ dpi. CamScanner turns scanned documents into PDF files, which are automatically uploaded to cloud services such as Box, Google Drive, Dropbox, Evernote and OneDrive. For improved security, you can add passcodes to documents.  Digital Camera Digital cameras – are used to capture pictures and videos individually. Later, these photo and video files can be transferred to a computer by connecting the camera directly with a cable, removing the memory card and inserting it into the computer, or through wireless data transfer such as Bluetooth. Once the photos are on the computer, they can be saved, edited, e-mailed, or printed. Digital Camera  Handheld Electronic Organizers are small mobile computers that accept input through a penlike instrument called a stylus that you use to write on the computer’s screen Handheld Electronic Organizers  Microphone Microphone – captures audio and sends it to a computer where it is converted to a digital format. Once the audio has been digitized, it can be played back, copied, edited, uploaded, or emailed. Microphones can also be used to record audio or to relay sounds live as part of a video chat or audio stream. Microphone  Joystick Joystick – is commonly used to control characters and vehicles in computer video games. Essentially, a joystick is a handle that pivots on a base and sends its angle or direction to the computer as data. Many video gaming joysticks feature triggers and buttons that can be pressed to use weapons or projectiles in games. Joystick  Web Camera Webcam - are different from digital cameras in two ways. Firstly, they cannot operate independently from a computer, and second, they have no inbuilt memory. Although webcams can capture photographs and videos, they are more often used to live- stream videos or facilitate video chats. Web Camera  Touch Screen a type of display screen that has a touch-sensitive transparent panel covering the screen. Instead of using a pointing device such as a mouse or light pen, you can use your finger to point directly to objects on the screen Touch Screen  Light Pen An input device that utilizes a light- sensitive detector to select objects on a display screen. A light pen is similar to a mouse, except that with a light pen you can move the pointer and select objects on the display screen by directly pointing to the objects with the pen Light Pen  Graphic/Digitizing Tablet Graphic Tablet – Also known as digitizers, graphic tablets are input devices used for converting hand- drawn artwork into digital images. The user draws with a stylus on a special flat surface as if they were drawing on a piece of paper. The drawing appears on the computer screen and can be saved, edited, or printed. Graphic tablets offer greater control and versatility for artists by allowing them to see their drawing appear live on their monitor as they create it. Graphic/Digitizing Tablet  Stylus a pointing and drawing device shaped like a pen. You use a stylus with a digitizing tablet or touch screen Stylus  Bar Code Reader is an input device used to scan a pattern of lines using optical sensing techniques. The line attern is coded information about the item to which it relates (e.g. the price and description of an item of merchandise) Bar Code Reader  Sensor is a device, which responds to an input quantity by generating a functionally related output usually in the form of an electrical or optical signal Sensor  Optical Character Recognition OCR is a foundational technology behind the conversion of typed, handwritten or printed text from images into machine-encoded text. Optical Character Recognition  Voice-Recognition System activated by user’s voice after voice has been programmed into the computer; currently accepts limited number of vocal commands Voice-Recognition System  Output Devices Output Devices - An output device is a piece of computer hardware that receives data from a computer and then translates that data into another form. That form may be audio, visual, textual, or hard copy such as a printed document. An Output device receives data from the computer.  Monitor Monitor – consists of a screen, circuit board, a power supply, buttons to adjust screen settings, and a casing that contains all of these components. A monitor displays data from a computer onto a screen so the user can interact with the data via a digital interface.  3 Types of Monitor CRT LCD LED  Types of Monitor Cathode Ray Tube (CRT) – is the technology used in traditional computer monitors and televisions. The image on a CRT display is created by firing electrons from the back of the tube to phosphors located towards the front of the display. Once the electrons hit the phosphors, they light up and are projected on the screen. The color you see on the screen is produced by a blend of red, blue, and green light, often referred to as RGB.  Types of Monitor Liquid Crystal Display (LCD) – is a flat panel display technology commonly used in TVs and computer monitors. It is also used in screens for mobile devices, such as laptops, tablets, and smartphones.  Types of Monitor Light-emitting diode (LED) - is a flat screen, flat-panel computer monitor or television. It has a very short depth and is light in terms of weight. The actual difference between this and a typical LCD monitor is the backlighting. LEDs use less power than CRT and LCD. Thus, it is considered as eco-friendly.  Printer Printer – a printer is used to create a hardcopy of the data sent from the computer to the printer. Printers take electronic data sent from a computer and generate a hard copy.  2 Types of Printer Impact Printer Non-impact Printer  Types of Printer Impact Printer – is a type of printer that works by striking a metal or plastic head against an ink ribbon. The ink ribbon is pressed against the paper, marking the page with the appropriate character, dot, line, or symbol. An  Types of Printer Non-impact Printer – a type of printer that does not operate by striking a head against a ribbon to produce characters on the paper. Examples of non impact printers include laser and ink-jet printers. The term non-impact is important primarily in that it distinguishes quiet printers from noisy (impact) printers.  Plotter Plotter is a device that draws pictures on paper based on commands from a computer. Plotters differ from printers in that they draw lines using a pen. As a result, they can produce continuous lines, whereas printers can only simulate lines by printing a closely spaced series of dots. Multicolor plotters use different-colored pens to draw different colors. Plotter  Speaker Speakers – are hardware devices that transform the signal from the computer's sound card into audio. Speakers create sound using internal amplifiers that vibrate at different frequencies according to data from the computer. Speaker  Headphones/Earphones Headphones/Earphones – produce audio from a computer through two individual headphones for a single listener. Also known as earphones, headphones allow you to listen to audio without disrupting other people in the vicinity. Headphones/Earphones  Speech Synthesizer Speech Synthesizer is a device that generates spoken language on the basis of written input. It is also known as Text-to-Speech. Speech Synthesizer  Microfilm or Microfiche are reduced sized photographic reproductions of printed information on film cards. The cards can be read using microfiche readers and printed using microfiche printers Microfilm or Microfiche  Projector Projector – as its name suggests, this output device "projects" computer images or video onto a wall or screen. Projectors  Input/Output Devices - a piece of hardware that is used for both providing information to the computer and receiving information  Modem the modem modulates the computer output to an acceptable signal for transmission and then demodulates the signal back for computer input Modem  Disk Drive computer hardware that holds and spins a magnetic or optical disk and reads and writes information on it. Disk Drive  Optical Disc a direct-access disk, has information recorded on it with a laser beam that burns pits into its surface Optical Disc  System Unit System Unit – the system unit, also known as a "tower" or "chassis," is the main part of a desktop computer. It includes the motherboard, CPU, RAM, and other components. The system unit also includes the case that houses the internal components of the computer. Some modern computers, such as the iMac, combine the system unit and monitor into a single device. In this case, the monitor is part of the system unit. While laptops also have built-in displays, they are not called system units, since the term only refers to desktop computers.  SYSTEM UNIT MOTHERBOARD CD-ROM POWER SUPPLY HARD DRIVE CPU FAN POWER CORDS HEAT SINK FLOPPY DRIVE VIDEO CARD ZIP DRIVE MODEM EXTRA CASE SOUND CARD FAN RIBBON CABLE  Central Processing Unit is the brain of the computer. Sometimes referred to simply as the processor or central processor, the CPU is where most calculations takes place.  Control Unit - Supervises or monitors the functions performed by the entire computer system according to conditions set forth by the stored program  Arithmetic/Logic Unit the part of a computer that performs all arithmetic computations such as addition and multiplication, and all comparison operations. The ALU is one component of the CPU (central processing unit).  Memory Unit is somewhat like an electronic filing cabinet capable of holding data or instructions  Memory Memory Unit ◼ ROM(Read Only) ◼ RAM(Random Access) contains the pre-programmed computer instructions such as the Basic Input Output System (BIOS) and special data that is used to store the programs the computer uses throughout and data that you will run. its processing.  Motherboard the main circuit board of a microcomputer. The motherboard contains the connectors for attaching additional boards. Typically, the motherboard contains the CPU, BIOS, memory, mass storage interfaces, serial and parallel ports, expansion slots, and all the controllers required to control standard peripheral devices, such as the display screen, keyboard, and disk drive. Collectively, all these chips that reside on the motherboard are known as the motherboard's chipset. Motherboard  Ports an interface on a computer to which you can connect a device. Personal computers have various types of ports. Internally, there are several ports for connecting disk drives, display screens, and keyboards. Externally, personal computers have ports for connecting modems, printers, mice, and other peripheral devices Ports  Storage Device Storage Devices – is a piece of computer hardware used for saving, carrying and pulling out data. It can keep and retain information short-term or long term. It can be a device inside or outside a computer or server. Other terms for storage device are storage medium or storage media.  Type of Storage Device There are two types of storage devices used with computers: ❖ Primary storage device, such as RAM, ❖ Secondary storage device, such as a hard drive. It can be removable, internal, or external.  Type of Secondary Storage: 1. Magnetic Storage Device 2. Optical Storage Device 3. Flash Memory Device 4. Cloud Storage 5. Paper Storage  Type of Secondary Storage: 1. Magnetic Storage Device - Magnetic storage is a form of non- volatile storage. This means that the data is not lost when the storage device is not powered. This is in contrast to volatile storage, which is typically used for the main memory of a computer system. Volatile storage requires a constant power supply - when a computer system is turned off, the data is lost. Magnetic storage is widely used because it is relatively cheap in comparison with other storage technologies. Magnetic storage is read-write, which makes it possible to re-use the storage capacity over and over again by deleting older data.  Type of Secondary Storage: 1. Magnetic Storage Floppy disk – A normal 3 ½ inch disk can store 1.44 MB of data. Hard drive – An internal hard drive is the main storage device in a computer. An external hard drive is also known as removable hard drive. It is used to store portable data and backups.  Type of Secondary Storage: 1. Magnetic Storage Magnetic strip – Magnetic tape drive stores video and audio using magnetic tape, like tape and video tape recorders. Super disk – A disk drive and diskette that can hold 120 MB and 240 MB of data.  Type of Secondary Storage: 1. Magnetic Storage Cassette tape – A magnetic storage device used for audio recording and playback. Zip diskette – Like a floppy diskette but more advanced. It usually hold 100mb of data.  Type of Secondary Storage: 2. Optical Storage Device – Optical storage is any storage type in which data is written and read with a laser. Typically, data is written to optical media, such as compact discs (CDs) and DVDs. Initially targeted as a potential replacement for hard disk drives (HDDs) in computing systems, the lack of growth in capacity compared to both hard disk and later solid-state flash storage has relegated optical storage use mostly to long- term archiving and data backup.  Type of Secondary Storage: 2. Optical Storage Device  Type of Secondary Storage: 2. Optical Storage Device Blu-ray disc – A digital optical storage device which was intended to replace the DVD format. CD-ROM disc – An optical storage device that is read-only or cannot be modified nor deleted. CD-R and CD-RW disc – CD-R is a recordable disc that can be written to once, while CD-RW is a rewritable disc that can be written to multiple times. DVD-R, DVD+R, DVD-RW and DVD+RW disc – DVD-R and DVD+R are recordable discs that can be written to once, while DVD-RW and DVD+RW are rewritable discs that can be written to multiple times. The difference between the + and – is in the formatting and compatibility.  Type of Secondary Storage: 3. Flash Memory Device – is now replacing magnetic storage device as it is economical, more functional and dependable.  Type of Secondary Storage: 3. Flash Memory Device Memory card – An electronic flash memory device used to store digital information and commonly used in mobile electronic devices.  Type of Secondary Storage: 3. Flash Memory Device Memory stick – is a digital data storage technology with up to 10 times the storage capacity of a 3.5 diskette. About the size of a flat AA battery, Memory Sticks are available in 4mb, 8mb, 16mb, 32m, and 64mb sizes.  Type of Secondary Storage: 3. Flash Memory Device Solid State Drive (SSD) – is a type of non-volatile storage media that stores persistent data on solid-state flash memory. Two key components make up an SSD: a flash controller and NAND flash memory chips. The architectural configuration of the SSD controller is optimized to deliver high read and write performance for both sequential and random data requests.  Type of Secondary Storage: 3. Flash Memory Device USB flash drive, jump drive or thumb drive – A small, portable storage device connected through the USB port. Is a plug- and-play portable storage device that uses flash memory and is lightweight enough to attach to a keychain. A USB flash drive can be used in place of a compact disc. When a user plugs the flash memory device into the USB port, the computer's operating system (OS) recognizes the device as a removable drive and assigns it a drive letter.  Type of Secondary Storage: 3. Flash Memory Device OTG Flash drive – is equipped with a standard USB connector on one end, and a micro-USB/Thunderbolt (apple) connector on the other end. In this way, you can connect the USB flash drive directly to your smartphone or digital camera without using a cable, allowing you to read and transfer data quickly and immediately. Nowadays, OTG Flash drive memory is available up to 1TB of storage and is much cheaper than your usual hard drives in the market.  Type of Secondary Storage: 3. Cloud Storage - Cloud storage is a cloud computing service in which data and files are stored offsite by a third-party provider and can be accessed through a public internet or dedicated private network connection.  Type of Secondary Storage: 4. Cloud storage – Data is managed remotely and made available over a network. Basic features are free to use but upgraded version is paid monthly as a per consumption rate.  Type of Secondary Storage: 5. Paper Storage – method used by early computers for saving information. Punch card – A piece of hard paper used to contain digital information coming from the perforated holes. The presence or absence of holes in predetermined positions defines the data.  Type of Secondary Storage: 5. Paper Storage – method used by early computers for saving information. Optical Mark Recognition (OMR) – A process of capturing marked data of human from forms like surveys and tests. It is used to read questionnaires with multiple choices that are shaded.