System software

System software

1. utility software

   • Utility software is software that manages various aspects of the system. The programs are designed to do one or two tasks, it interacts with the computer hardware.
   • EXAMPLES OF UTILITY SOFTWARE:File Compression, Disk Defragmentation, File Repair, Disk Copying, Disk Formatting, Disk Backup / Restore, Anti-Virus
     • File Compression
       • Reducing the size of the file by performing an algorithm on the original data Lossless The original file can be re-created as no data is lost. Lossy Some of the original data is lost and the original file can not be re-created
     • Disk Defragmentation
       • When a hard disk drive is new – files get added onto the disk in order – very much like starting with a blank piece of paper and adding to it. As files are deleted – this leaves gaps When new files are saved – the files fill the gaps and become fragmented. Defragmentation software groups fragmented files back together
     • Encryption
       • Encryption means to scramble data in a way that it is unreadable to anybody who doesn’t have a key to be able to unscramble this. Data is encrypted using a key and then decrypted using a key Data is encrypted so that it is unreadable if anyone is to intercept it
     • Back-ups
       • Completed to ensure there is a way of restoring files/data/programs in case of computer failure. Copies of data and/or software are taken regularly and usually stored in a different location. Ensures that if computers are stolen or damaged in for e.g. a fire or a natural disaster that data can be restored and a company do not lose much money
         • Back-up types
           • Full
             • A copy of all data and software on the hard disk drive / server is copied to a backup medium (e.g. an external hard disk drive / DVD-R) and the medium is kept at a different location Take a long time to complete (usually overnight) Recovery takes a long time as it restores all data and programs
           • Incremental
             • A full backup is made initially. Each night only the files which have been changed since the last incremental back-up are copied. Much faster to complete that full back-ups. Takes much longer at restoring than a Full Back up as the full back up would need restoring first and then every incremental back-up since the last full back up.

2. operating system

   • System software
     • Systems software is a type of software that controls the computers hardware. It provides an interface between the user of the computer and the hardware. An Operating System is a type of Systems Software.
   • Application software