system software

system software

1. operating system

2. utility software

3. utility software

   • disk copying
   • disk formating
   • disk fragmentation
     • 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
   • file repair
   • file compression
     • reduces the size of the algorithm in the original data
       • lossless: the original file can be re-createde as no data is lost
       • Lossy: Some of the original data is lost and the original file can not be re-created
   • back up/ restore
     • 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. Incremental or full
       • incremental: A full backup is made initially Each night only the files which have been changed since the last incremental back-up are copied
   • anti virus
   • 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

4. operating system

5. device drivers

   • graphics card driver
   • network interface card driver