1.5 Operating systems and utility software Flashcards
What is an operating system
An operating system (OS) is software that provides an interface between the user and the hardware in a computer system
An operating system hides the complexities of the hardware from the user, for example:
A user does not need to know ‘where’ on secondary storage data is kept, just that it is saved for when they want it again
User interface
Allows user to interact with the OS
Command line interface (CLI)
A Command Line Interface (CLI) requires users to interact with the operating system using text based commands
GUI
A Graphical User Interface (GUI) requires users to interact with the operating system using visual elements such as windows, icons, menus & pointers (WIMP)
Memory management
Memory management is a process carried out by the operating system allocating main memory (RAM) between different programs that are open at the same time
The OS is responsible for copying programs and data from secondary to primary storage as it is needed
Multitasking
Multitasking is a process made possible by the OS simultaneously managing system resources (memory, CPU etc) to give a user the perception of being able to use multiple programs at the same time
Peripheral management
Peripheral management is a process carried out by the operating system managing the way peripherals (hardware) interact with software
Peripheral management makes plug-and-play (PnP) functionality possible, automatically detecting and configuring new peripherals without the need for manually installing device drivers or power cycling the system
Device drivers
A device driver is a piece of software used to control a piece of hardware
Peripherals require device drivers in order to be used by the operating system
The OS has generic device drivers built in which makes basic compatibility possible and enables plug-and-play (PnP)
Device drivers are OS specific and are regularly updated
File management
File management is a process carried out by the operating system creating, organising, manipulating and accessing files and folders on a computer system
The OS manages where data is stored in both primary and secondary storage
File management gives the user the ability to:
* Create files/folders
* Name files/folders
* Rename files/folders
* Copy files/folders
* Move files/folders
* Delete files/folders
The OS allows users to control who can access, modify and delete files/folders (permissions)
The OS provides a search facility to find specific files based on various criteria
What does an OS do
o User interface
o Memory management and multitasking
o Peripheral management and drivers
o User management
o File management
What is utility software
Utility software is software designed to help maintain, enhance and troubleshoot/repair a computer system
Utility software is designed to perform a limited number of tasks
Utility software interacts with the computers hardware, for example, secondary storage devices
Some utility software comes installed with the operating system
What does utility software have
o Encryption software
o Defragmentation
o Data Compression
Defragmentation software
- If a file is fragmented, the disk head will have to move to many different locations to access the file- increasing load times
- Defragmentation will reorder fragmented files so that they are stored contiguously (together) - this decreases load times
Compression software
- Utilities such as WinZip enable users to compress and decompress files or folders
- This reduces the amount of storage space needed on a disk
- If sending the files, it reduces the amount of data that is sent
- Compression may allow attachments to be sent via email that would otherwise have been larger than a file-size limit
- More data can be stored on backup media
- Uses either lossy or lossless compression
Encryption software
- Encrypt entire hard disks so that the data cannot be read if the computer is stolen
- Encrypt files and folders on a portable disk such as USB removable storage
- Encrypt communication with websites
- Encrypt data in an organisation’s database – especially sensitive data such as passwords
Backups
- A backup is a copy of a computer systems files and settings stored externally. This means that data can be recovered in the event of data loss.
- A backup utility is software with facilities such as scheduling of regular back ups, creating rescue disks and options for FULL or INCREMENTAL backups.
Full backup
A copy is taken of every file on the system. They often use a lot of storage space. Takes a long time but is faster to restore from
Incremental backup
Only files created and edited since the last backup are copied. Use less storage space and quicker to create. But, a full system restore is slow and requires the last full backup to be restored, followed by each incremental
