System Technologies: Software PDF

System Technologies: Software 3 Distribution models for Software / Types of Software: The developers can decide to either use propriety, open source, shareware and freeware distribution. (SaaS is another distribution model, and is discussed as part of Cloud Applications at th...

System Technologies: Software 3 Distribution models for Software / Types of Software: The developers can decide to either use propriety, open source, shareware and freeware distribution. (SaaS is another distribution model, and is discussed as part of Cloud Applications at the end of the document – Form 5)  (Free) Open-Source Software (FOSS) o Software made available with a license that allows you to access and modify the source code to add new features. (You may not sell the software). o E.g. OpenOffice, Linux, VLC Media Player o Advantages:  It is free (or low cost), which saves you money.  Because the source code is available to anyone, the public can collaborate and fix bugs.  Collaborators can improve the performance and even add features. o Disadvantages:  Not as user friendly.  Lack of support and liability.  Exposed to viruses and other cyber-attacks.  Proprietary software o Software owned by the company, and you must buy a license to use it. Only the company can make changes to the source code. o Advantages:  The software is stable, and it has already been tested.  support is easily available. o Disadvantages:  You must buy the product (license).  If there is a technical issue, you will have to wait for the developer to fix the problem and release a patch.  Software may not be shared.  No access to the source code. pg. 1 System Technologies – Software (PBHS)  Categories of proprietary software: o Shrink-wrap / click through– A type of proprietary software that you buy in stores, (lately we download it after receiving a code when payment was made). It may not be copied and may generally only be used on one computer/device. Requires you to agree to the end user license agreement (EULA). Eg. Adobe Photoshop, Microsoft Windows o Shareware – A type of proprietary software that you can download and try before you buy. Usually limited in features and/or time and uses the try before you buy concept. Eg. WinZip, Microsoft 365  Advantage: Gives the distributor exposure and it allows the user to decide if they want to buy the product. o Freeware – A type of proprietary software that you can freely download and copy/share (multiple times) with your friends (although developers keep the rights of the software). NotePad++, Adobe Reader, Skype  Advantage: Is free and easily accessible.  Disadvantage: Can contain malware such as viruses and Trojans. It also has limited support. Licensing of Software  Single user/device license – one user or device only  Multi-user license – for multiple users/multiple devices.  Site license – a license that can be installed on multiple devices – normally a company (common group of users on same location).  EULA (End User License Agreement): This is the legal agreement (terms and conditions) you acknowledge to when using the software (adhere to the license type of the software).  Intellectual property Products or material created by the mind of a person. Not just physical objects – words of a song or the music or an essay is intellectual property. pg. 2 System Technologies – Software (PBHS)  Types of Software License Agreements to protect Intellectual property:  Copyright Only the owner or creator of the intellectual property can change and distribute the work. The owner can grant permission or a license to others to use or distribute the work. (We may use photos or sections BUT all must the referenced for all to see that it is not your original work. General rule – no more than 10%)  Copyleft Licenses that allow for work to be copied or edited and distributed for non- profit reasons – IF they follow certain rules. (Usually associated with use in education).  Creative commons This license allows for editing, distribution and changing the original if the creator is always acknowledged. There are many different types of creative commons, e.g. non-commercial, attribution, etc.  GPL General public license – user may edit and distribute, but the new receivers must also be able to do the same. Used in all OSS. Also used for freeware. Piracy The illegal copying, distribution, or use of software (intellectual property).  Why shouldn’t piracy take place? The goal of copyright is to give people a reason to create and invent new things. If the creator cannot make money from his intellectual property, it will not be created. Installing, Uninstalling and Updating of Software  Installing Software The process by which a new program is being added to your PC. Usually run by a program (Wizard) that loads or unpacks numerous files belonging to that program. From CDs or download installation files from the internet. Sometimes an activation key is necessary to unlock the software. Might have to accept the terms and conditions  EULA.  Uninstalling software Removing the software from the computer. Do not just delete the executable file (or shortcut). pg. 3 System Technologies – Software (PBHS)  Use the uninstall feature to make sure ALL files (that were added during installation) are deleted.  Updating software o To fix bugs (problems) with the version installed. o To add new features. o To update security features. Different types of updates: o Patch: a small update to fix bugs in software. o Service Pack: is an installable package that consists of patches that were released over a period of time. Software can be classified as:  System software A set of programs which manages and controls the operation of a computer. (Controls all hardware and software actions - no computer can run without system software as it controls the computer on the lowest level.)  Application Software Programs used by the user to do specific tasks. System software made up of:  The OS (Operating System) System software that controls the hardware and software of the computer and provides the GUI for users to interact with the computer. (OS is also responsible for many other functions listed and discussed in section lower down).  Utility programs Software that performs specific tasks to manage, maintain and secure the computer. Examples: o Archiving Outdated, but important files can be compressed and stored on a secondary storage device where they can be retrieved when necessary. o Backup Duplicate copy of documents/files kept off site to be re-used in case the working files get lost/damaged. An online backup service can also be used. NOTE it is not syncing. pg. 4 System Technologies – Software (PBHS)  o Disk clean-up A utility program that removes the following:  Temporary files downloaded from the internet.  Deleted files and folders from the recycle bin.  Temporary files created by windows that are not used anymore.  Components of windows that are not used.  Installed programs that you no longer or seldom use. o Compressing (WinZip, WinRAR) Software to reduce the size of a file (saves files in a smaller format). It needs to be uncompressed (extract) again to be able to use it again. Different types of compression (Lossy / lossless  refer to Grade 11 notes) Reasons for compressing files and folders:  To reduce the size of e-mail file attachments.  To save storage space.  To minimize the use of data when uploading and downloading files over the internet. o Disk Defragmentation (traditional Hard Disk Drives only) Disk Defrag is a tool that re-organises clusters of files to be adjacent to each other. When clusters are adjacent to each other, it speeds up access time (transfer time) from the hard drive when retrieving the file (the read/write head does not have to jump to different positions). Defrag does not create more storage space on the hard disk! What is fragmentation? When the clusters belonging to a single file (parts of files) are not adjacently stored in storage. This slows down access time to/from storage on the disk because the read-write head must jump to different positions (sectors) on the hard disk platter. How do the clusters of files become non-adjacent? Because of the constant editing, deleting, and adding of files. Why is fragmentation a problem only with traditional HDD and not SDD? SDDs store data electronically while HDD use a read-write arm that must move to a specific platter, track, and sectors on the magnetic disc to access the different clusters of the file. pg. 5 System Technologies – Software (PBHS)   Device drivers Programs that allow the OS to communicate with and control hardware devices connected to your computer. o Automatic vs Manual driver installation: Plug-and-play – refers to the technology whereby devices that are added or connected to a computer are automatically ‘detected’ (drivers found) and the PC is configured to use them right away without rebooting (Automatic driver installation). If drivers are not present as part of the OS, you will be prompted to load them (manual driver installation). This was done from a CD but lately we browse the internet to find and download the drivers. o Hot-swappable A device can be connected and disconnected while the computer is on. (E.g. flash drives, printers, mice, keyboard). (It is the ability to ‘plug-and-play’ without switching the computer off.) Types of OS:  Embedded operating system Operating systems that are stored on internal memory chips (not loaded from a storage disk). They are designed for a single purpose (task) in a device such as ATM’s POS, e-readers, traffic lights, TV’s.  Network Operating System An operating system which has the ability to control and manage shared resources, communication, security and multiple users in a network environment (web servers, mail servers, virtual servers). e.g. Unix, Linux, Microsoft Server  Stand-alone Operating systems that runs on PC’s, laptops and notebooks and manages the hardware and software of the device. pg. 6 System Technologies – Software (PBHS) System Software: Operating System The functions of an Operating System: 3  Provides a GUI A graphical user interface makes use of visual controls to allow the user to interact with the computer and with programs on the computer.  Input / Output control (Device management) A function of an operating system whereby it manages input and output of the computer and how programs use the input and output devices. (The operating system is assisted by device drivers.)  Disk management (Storage / File System management) A function of the operating system that manages storage. It organizes files on the storage device and how to access files on the storage device. (FAT table and Indexing is managed by this function).  Memory management (RAM) A function of an operating system which manages the memory (RAM) to control how programs use it. (Allocates virtual memory if needed. Form 4)  Process and task management (CPU) A function of an operating system whereby it manages the CPU and how it runs programs and utilises resources required by these processes. (Processing techniques are part of this function – Form 4) How does OS save files and information about files?*  FAT (File Allocation Table) It serves as an index that records the locations of files and folders stored on a storage medium. The FAT contains entries for each file and folder, indicating where each file's data is stored on the disk. This information helps the operating system locate and access files when needed.  INDEXING of Files*: The OS uses an index (which is a database) that stores not just files and folder names, but other details such as size and date modified, as well as the text inside the files (known as meta-data). Used when searching for a file. pg. 7 System Technologies – Software (PBHS)