AS Lvel CS (9618) 5 System Software

CMOS

complementary metal-oxide semiconductor.

Operating system

software that provides an environment in which applications can run and provides an interface between hardware and human operators.

HCI

human–computer interface.

GUI

graphical user interface.

CLI

command line interface.

Icon

small picture or symbol used to represent, for example, an application on a screen.

WIMP

windows, icons, menu and pointing device.

Post-WIMP

interfaces that go beyond WIMP and use touch screen technology rather than a pointing device.

Pinching and rotating

actions by fingers on a touch screen to carry out tasks such as move, enlarge, reduce, and so on.

Memory management

part of the operating system that controls the main memory.

Memory optimisation

function of memory management that determines how memory is allocated and deallocated.

Memory organisation

function of memory management that determines how much memory is allocated to an application.

Security management

part of the operating system that ensures the integrity, confidentiality and availability of data.

Contiguous

items next to each other.

Virtual memory systems

memory management (part of OS) that makes use of hardware and software to enable a computer to compensate for shortage of actual physical memory.

Memory protection

function of memory management that ensures two competing applications cannot use same memory locations at the same time.

Process management

part of the operating system that involves allocation of resources and permits the sharing and exchange of data.

Hardware management

part of the operating system that controls all input/output devices connected to a computer (made up of sub-management systems such as printer management, secondary storage management, and so on).

Device driver

software that communicates with the operating system and translates data into a format understood by the device.

Utility program

parts of the operating system which carry out certain functions, such as virus checking, defragmentation or hard disk formatting.

Disk formatter

utility that prepares a disk to allow data/files to be stored and retrieved.

Bad sector

a faulty sector on an HDD which can be soft or hard.

Antivirus software

software that quarantines and deletes files or programs infected by a virus (or other malware). It can be run in the background or initiated by the user.

Heuristic checking

checking of software for behaviour that could indicate a possible virus.

Quarantine

file or program identified as being infected by a virus which has been isolated by antivirus software before it is deleted at a later stage.

False positive

a file or program identified by a virus checker as being infected but the user knows this cannot be correct.

Disk defragmenter

utility that reorganises the sectors on a hard disk so that files can be stored in contiguous data blocks.

Disk content analysis software

utility that checks disk drives for empty space and disk usage by reviewing files and folders.

Disk compression

software that compresses data before storage on an HDD.

Back-up utility

software that makes copies of files on another portable storage device.

Program library

a library on a computer where programs and routines are stored which can be freely accessed by other software developers for use in their own programs.

Library program

a program stored in a library for future use by other programmers.

Library routine

a tested and ready-to-use routine available in the development system of a programming language that can be incorporated into a program.

Dynamic link file (DLL)

a library routine that can be linked to another program only at the run time stage.