Systems Software

Systems Software

1. Utility Software

   • Utility software has a specific job to do regarding the computer's operating performance.
   • Anti-virus software
     • Anti-virus software prevents viruses as long as the software has been updated which will allow it to prevent new viruses
     • Does not stop hackers
   • Enryption
     • It means to scramble data in such a way that only people with the right key can decrypt it.
     • Data is encrypted so that it is unreadable if anyone is to intercept it.
   • Defragmentation
     • Defragmentation is when it groups different types of data together so that the disk can work faster.
       • For example: it groups all the empty spaces together.
   • Back ups
     • Full
       • A full copy of all the data and software is completed
       • The full back up usually takes a long time to complete (usually overnight).
       • Recovery takes a long time as it restores all data and programs.
     • Increment
       • A full back up is made initially.
       • Overnight its only the things that have been changed since the full back up are saved.
       • Much faster to complete than full.
       • It takes longer to restore as the data from the last full back up is restored first then the data from the increment back up.
     • Completed to ensure there is a way of restoring files/data/programs in case of computer failure.
   • Compression
     • Lossy
       • This is when the file is compressed and the quality of the file is lost.
       • The data that has been deleted cannot be restored unless you go back to the original file.
     • Lossless
       • The data that has been deleted can re-stored as no data is lost.
     • Reasons compression is useful: 1) less storage space is needed 2) it is faster to download and upload the file 3) better performance is achieved when streaming audio or video files

2. Operating System

   • The operating system is a collection of programs that control the hardware in a computer or device.
   • At the heart of the operating system is the Kernel.
     • The kernel is a computer program that is the core of a computer's operating system, with complete control over everything in the system. On most systems, it is one of the first programs loaded on start-up.
   • Interface
     • Command line
       • Allows the user to interact directly with the computer system by typing in commands.
     • Menu
       • It gives a list of the possible actions that can be carried out. If an action isn't on the menu then the user cannot do it. Used for when a small number of commands have to be done.
     • Graphical user
       • It is a 'friendly' way for people to interact with the computer because it makes use of pictures, graphics and icons.
     • An interface allows the user to interact with the computer
   • File management
     • It is normally organized into folders and subfolders for easy user navigation and usage.
     • It allow users to create, modify, copy, delete and move files, users to search for a particular file, keep track of the location of files, keep track of free space, allow users to restore deleted files, prevent conflicts when two users on a network, attempts to modify the same file, maintain access rights to files.
   • Memory management
     • When the program finishes or data is no longer needed the memory management system frees up that space for reuse.
   • Multi-tasking
     • It allows a computer to run more than 1 program at the same time – or at least appear that they are.
     • It works out the most efficient way for the programs to run.
   • User management
     • Enables a network administrator to set different access rights for different users.
     • It allows the administrator to set default logout times based on inactivity,

3. Presentation types

   • Proprietary source
     • Advantages of propriety sourc:e: Someone owns the product and takes responsibility for the quality; There will be ongoing updates to fix issues, There will be technical support available, Large user base, Training courses.
     • Disadvantags of propriety source: The cost of support and updates can make the software quite expensive; The software may not be modified by the end user to meet their needs.
     • Proprietary software is software where the source cannot be changed and is legally remains the property of the organisation, group or individual who created it.
   • Open source
     • Advantages of open source: the software can be adapted to meet individual needs, Community of enthusiastic developers
     • Disadvantages of open source: the software can be adapted to meet individual needs, Community of enthusiastic developers
     • It is a software where the source code is publicly available so that anyone can alter it.

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