ICT - System software

System Software

The Purpose and Function

• The operating system can be referred to as system software. The main purpose of the operating system is to provide an interface to allow users to communicate with the computer system. It also manages and controls all of the hardware and software. The main functions od the operating system include:
• interface- allowing communication between the user and the computer
• memory management- allocating internal memory (RAM) to programs and data that the user is currently using; retrieving and storing data on the external memory devices
• resource management- controlling peripheral (input and output) devices and handling user requests for these devices
• execution- 'booting up' the computer when is it switched on
• error handling- dealing with errors that occur when programs are running and communicating the responses to software developers and the user
• system security- checking and controlling user access to programs and data to prevent unauthorised access

Graphical User Interface (GUI)

• Features of a GUI include-

Windows

• each folder, program or document opened by a user is displayed in a separate window
• windows can be minimised or maximised
• the window that is maximised is described as the 'active' window

Icons

• small graphics representing a program, file or a tool from a toolbar
• icons reside on the desktops shortcuts to folders, programs or documents
• when you double-click and icon the folder, program or document opens
• can be customised is appearance and arranged by size or date modified

Menus

• can be 'pull down' or 'pop up'
• each menu provides a list of options for the user to select from
• can be customised to show a full list of options or a smaller list of options

Pointers

• shows the position of the cursor on the screen