23 terms

1.7 Systems software

Purpose of System Software
- To control the hardware.
- To provide an interface between the user and the hardware.
- To perform 'housekeeping tasks' to help ensure smooth running of the system.
- To provide a platform on which applications software can run.
Application Software
The everyday programs that we use to create documents and perform tasks
Operating System(OS)
The main system software for a computer system, controlling the hardware and providing a platform for applications.
Functions of a Operating SYSTEM
1. User interface
2. Memory Management
3. Multitasking
4. Peripheral Management
5. Drivers
6. User Management
7. File Management
User Interface
Is what we use to interact with the computer system.
Graphical User Interface(GUI)
This is type of interface that uses lots of icons, menus and windows for us to click and open.
Command-Line Interface(CLI)
Its requires the user to type in the program commands for the taska they want to perform
Natural-Language Interface(NLI)
It requires the user to use spoken commands.
Memory management
The process of controlling and coordinating computer memory, assigning portions called blocks to various running programs to optimise overall system performance.
The illusion that more than one task is being performed at once. This is achieved by giving very brief time slices to each application in turn and moving between them in a circuit. The changes happen so quickly, the user is typically unaware of them.
Peripheral management
Controlling external devices such as mice, keyboards, webcams and printers. This is often done using drivers which provide information about the device to the operating system.
Small utility programs that give the operating system information about new external hardware.
User management
One computer can be used by several people (or user). Each user has their own account. Their files are kept separate and are not accessible to others in other accounts. Different levels of access and control can be assigned to specific users.
File Management
Creation of a folder system in which files are organised. Files can be renamed, moved and deleted. File extensions help tell the operating system, applications and users what type of file each one is.
Utility System Software
Helps to manage, maintain and control the computers resources.
Encryption Software
Software that encrypts data for secure transmission (see encryption in the networks section).
Moving parts of files on a hard drive to ensure that large files are kept together in adjacent sectors of the drive rather than being split up (fragmented) in various locations.
Data Compression
Making files smaller. This speeds up downloads and makes them quicker to send via email.
Lossy Compression
- This reduces the size of a file by removing some of the data in the file.
- Is used mainly for audio, video and image files. It is mostly used when streaming or transmitting them.
Lossless Compression
- Does not remove any of the original data from the file.
- The file can be restored to its original form.
Making a copy of working files to a safe location. These can be copied back to the system if the originals are damaged or lost.
Full Backup
Backing up an entire set of files.
Incremental Backup
Backing up only the data that has been changed since the last backup.