Zusammenfassung der Ressource
1.7 System Software
- system software is software
designed to run and maintain a
computer system
- What is an operating
system?
- The main functions of an Operating system are:
- communicate with internal and external hardware via the device driver.
- Provide a user interface, allowing the user to interact with the computer and vice-versa
- provide a platform for different applications to run
- Allow the compuer to multi-task by controlling memory resources and the CPU
- Deal with file management and disk management
- The operating system is the
software that manages the
hardware on the computer.
Examples Windows, Linux,
Android, Apple OS X and IOS
- Operating system manages Hardware and run software
- What is a GUI ( Graphical user interface)?
- A GUI is a visual interface that
operating systems use. They
consists of icons, pointer and
menus
- What is Utility software
- Utility software/tools add extra functions to an operating system and add the
ability to carry technical tasks. Examples: Disk Management, Backups, Computer
Analysing, Disk Compression and defragmentataion, Anti-virus
- A backup is a copy of a computer
system's file and setting stored
externally. This means data can be
recovered in the event of data loss. Data
loss can happen for may reasons there
are theft, flood, malware, hardware
failure and accidentally deleting the file
yourself
- A backup utility is software with facilities such as
scheduling of regular backups, creating rescue disks, disk
images, and options for full or incremental backups:
- A full backup is where a copy is taken of every file on
the system. They often use a lot of storage space. A
full backup can take a long time to create, but is
faster to restore them
- A incremental backup are where only the files created or edited
since the last backup are copied. They use less storage space and
are much quicker to create. But, a full system restore is slow- the
last full backup must be restored, followed by every incremental
backup since that point.
- The other types of utility are:
- Compression Software
- Compression software reduces the size of files so they take up less
disk space. It's sued loads on the internet to make files quicker to
download. Standard files formats include .zip and .rar. Compressed
files need to be extracted before they can be used
- Encryption Software
- Encryption software scrambles(encrypts) data to stop
third-parties from accessing it. Encrypted data can be
decrypted using a special ' Key'
- Defragmentation
- files are stored on a hard disk in available spaces. ideally, entire files
would be stored together, However, as files are moved, deleted and
change size, lots of small gaps begin to appear on the disk. When
writing files to the disk, to OS splits files into smaller blocks to fill up
the gaps
- Over time, the disk becomes more and more fragmented. This akes reading and
writing files lsower as the read/write head has to move back and fourth across
the disk
- Defragmentation software
reorganises data on the hard
drive to put fragmented files
back together. It also moves files
to collect all the free space
together. This helps to prevent
further fragmentation.
- As SSDS use flash storage with no moving parts,
fragmentation doesnt cause them any problems- they can
access data just as quickly however it's arranged. In fact as
SSDs have a limited number of read/writes, defragmenting
them can actually shorten their lifespan
- What is application software
- Application software allows users to
carry out useful such as writing reports,
surfing the web or using email
- Main types of application software:
- +Word processing
- + Desktop publishing
- + Spreadsheet
- +Database Management
- + Presentation/Slideshow
- +Photo-Editing/Graphics
- +Video Editing
- +Web Browsers
- +Gaming Software
- Operating systems use device drivers
software to communicate wiht internal
hardware or peripherals connected to the
computer system
- 1)Every piece of hardware connected to the computer system requires a device
driver. Drivers act as 'translator' for the signal between OS and hardware
- 2) When a computer is booted u, the OS will
choose the correct device drivers for the
hardware it detects. If new hardware is
connected to the computer, the computer will
install new driver.
- 3)Device manufacturers may release updates to device drivers in
order to fix bugs, add features or improve the performance of
their hardware. updates can be installed automatically by the OS
or manually by the user.
- The OS allows Multi-tasking by managing Resources
- The OS handles File and Disk Management
- Computers store date as files. Images, music, videos and spreadsheets are all
just collections of data. Files extensions (for example .jpg, .mp3, .mpeg) tells
the computer which software should be used to open the file
- The OS is responsible for file management -
the organisation of data into a usable
hierarchical structure. It also deals with the
movement, editing and deletion of data
- The OS manages the hard disk. It splits the
physical disk into storage sectors, decides
which would be placed in adjacent sectors, but
this isn't always possible
- The OS also organises and
maintains the hard disk with
utility software like
defragmentation software
- operating systems provide a platform, to run applications
(by configuring hardware so they can use it, and giving
access to the CPU and memory).
- Operating systems that can run multiple applications at the
same time are called multi-tasking OSs.
- The OS helps the CPU carry out multi-tasking by efficiently managing memory
and CPU processing time