Define operating system
A software that manages a computer system. It is loaded by the bootstrap loader. One of its primary functions is to manage resources
What resources does the operating system manage
Peripherals
Security
Printing using spooling
Backing storage
Random Access Memory (RAM)
Processes
How does the operating system manage peripherals
- communicates with and sends data output to a primer/monitor/other valid output device
- communicates with and receives data input to a keyboard/mouse/other valid input device
How does the operating system manage security
- Allows creation and deletion of user accounts
- allows users to logon and change passwords
How does the operating system manage printing using spoiling
- stores data in a hard disk/in memory/stored in a queue
- prints document when printer is free-in correct order
Benefit of spooling
User can carry on working/log off when waiting for job to print
How does the operating system manage backing storage
- ensures data is stored and can be retrieved correctly from any disk drive
- creates and maintains filing system such as file allocation table (FAT) or new technology file systems (NFTS)
Organises files in a hierarchical directory structure
How does the operating system manage RAM
- ensures that programs/data do not corrupt each other
- ensures that all programs and data including itself, are stored in correct memory locations
How does the operating system manage processes
- ensures that different processes can utilise the CPU and do not interfere with each other or crash
- On a multitasking O/S, ensures that all tasks appear to run simultaneously
What does the user interface provided by the operating system do (8 points)
- allows copying, deleting, moving, sorting and searching of file or folders
- Allows access to system settings such as hardware
- Provides a command line interface
- allows users to have more than one window open
- provides a graphical user interface (Windows, Icons, Menus, Pointers)
- provides user with error/help messages
- allows customisation of interface e.g change desktop back/layout
- allows user to switch between tasks (programs/windows)
Define utility software (utilities)
Software programs that add functionality to your computer or help your computer perform better
What does the utility software do
- file indexing
- file conversion
- defragmentation
- compression
- task management
- disk scanning and repair
- antivirus software
- backup
- firewall
Define file indexing
A computer file with an index that allows easy random access to any record given its file key
Define file conversion
Conversion of files from one format to another such as a sound file from WAV to MP3
Define defragmentation
The process where files are physically re-arranged on disk so that they are no longer fragmented, and the parts of each file are stored together
Define compression
The process of making a file size smaller. This may be advantageous as it allows more data to be stored on the disk, and files may also be transferred more quickly. The two primary methods are called lossy and lossless
Define task management
View each of the tasks (processes) and the overall performance of the computer.
View how much memory a program is using, stop a frozen program, and view available system resources
Define disk scanning and repair
The utility software scans the hard drive and, where necessary, attempts to repair errors in files stored on the hard disk
Define antivirus software
Designed to prevent viruses, worms and Trojan horses from attacking a computer as well as remove any malicious software code that has already infected a computer. Most utilities now bundle in anti-spyware and anti-malware capabilities
Define backup
Copies data to a storage medium. At periodic intervals, a backup of the entire hard drive or of selected files and folders can be performed. These programs can also be set up to back up files automatically when they have been updated and saved.
Define firewall
A network security system that monitors and controls incoming and outgoing network traffic based on predetermined security rules. Typically establishes a barrier between a trusted internal network and an untrusted external network, such as the internet.
