Hardware and software

Hardware and software

1. Hardware

   • electrical or electro-mechanical parts
   • input devices
   • output devices
   • storage devices

2. Software

   • System software
     • operating system
       • set of programs between application software and computer hardware
       • functions
         • resource management
           • managing computer hardware
         • provision of user interface
           • (e.g. Windows) to allow users to perform tasks, e.g. running application software, changing settings on the computer, downloading and installing new software
     • = software needed to run the computer's hardware and application programs
     • utility programs
       • designed to optimise the performance of computer
         • OR perform tasks
           • backing up files
           • encrypting data before transmission
           • providing a firewall
       • disk defragmenter
         • a program that reorganises a hard disk Files split up into blocks and stored all over the disk get recombined in a single series of sequential blocks - Makes reading a file faster
       • virus checker
         • checks hard drive, and possibly incoming emails and internet downloads, for viruses and removes them
     • libraries
       • in windows, often have a .dll extension
       • ready-compiled programs
       • grouped together in software libraries
       • Many compiled languages have their own libraries which can be invoked in the user's programs
     • programming language translators
       • compilers
       • interpreters
       • assemblers
       • translate program code into machine code
   • Application software
     • general-purpose
       • e.g. word processor, spreadsheet, graphics package can be used for many different purposes
     • special purpose
       • performs a single specific task or set of tasks
       • e.g. payroll and accounts packages, hotel booking systems, fingerprint scanning systems, browser software
       • Software may be bought "off-the-shelf", ready to use, or it may be specially written by a team of programmers for a particular organisation
     • custom-written (bespoke)
       • more expensive than ready-made package