Systems Software

What are the 7 functions of an OS? (FUMDUMP)

File management; User interface; Memory management; Drivers; User management; Multitasking; Peripheral management

What is file management?

The OS creates and maintains a file system. The user can: (Re)name files; Assign files to folders; Move files; Save files; Edit files; Copy & paste files

What is the User Interface (UI)?

The UI receives input and outputs data to the user. Allows for communication with the hardware.

What are the 2 types of UI?

Graphical User Interface (GUI) and command line

What is the GUI?

A graphic-based UI - uses windows, icons and pointers to control the computer.

Give 1 advantage and 1 disadvantage of GUI.

• Easy to use; + Powerful; - Heavy resource usage; - Slow

What is command line?

A text-based UI - commands are entered directly into the system.

Give 1 advantage and 1 disadvantage of the command line interface.

• Low resource usage; + Fast; - Hard to understand/use

What is memory management?

The OS manages the RAM, moving the application from secondary storage to RAM when it is loaded. It also operates the VM.

What is a driver?

A program which allows the computer to communicate with an external device.

What is user management?

The OS: Sets up user accounts; Sets up passwords/security; Sets up access rights for each user (user, admin, guest etc.)

What is multitasking?

The OS can only perform one process at a time, but can appear to do multiple by managing the memory.

Give an example of multitasking.

Having Minecraft and Youtube running at the same time.

What is peripheral management?

Managing devices connected to the computer like keyboards and printers.

What does the OS do in peripheral management?

Receives data from input devices; Sends data to output devices; Allows for communication between input and output devices

What is utility software?

Software which maintains the system and keeps the computer running smoothly.

What is fragmentation?

Data fragments are spread over a hard drive, so it takes longer to read it

How does fragmentation occur?

Files are deleted; New files added are bigger than gaps left behind; Files are split up

What is defragmentation?

Files are moved to be stored contiguously.

What is the process of defragmentation?

Collate free space at end; Collate file fragments together; Store files contiguously

What is the benefit of defragmentation?

The needle doesn't have to move as far so faster to access files; Don't have to search for rest of file; Less time to save new data because large spaces of free space, so can be stored contiguously.

What is compression?

Reduction of file size to save space on secondary storage by removing quality.

What is the process of compression?

Algorithm is used to remove repeated/unnecessary data

What is the difference between lossy and lossless?

Lossy loses quality permanently, lossless is temporarily lost

What does encryption software do?

Algorithm used to scramble data into cypher text; Encrypted data is unintelligible; Keys are used to encrypt/decrypt data

What are the two software licences?

Open source and proprietary

What is open-source software?

Software distributed with no restrictions; Users can see source code; Users can modify it; Usually free; Issues with DPA (less secure)

What is proprietary software?

Software distributed with restrictions; Users buy licence to use it; Users cannot see source code; Cannot be modified; Usually paid for