SLR1.5 Flashcards
what is an operating system
- provides a platform on which users can run programs
- software that tells the hardware what to do
- controls the operations of the computer
utility software
used to maintain the computer system
types of user interfaces:
GUI (graphical user interface)
command line
menu
natural language
GUI
graphical user interface
the way in which you interact with a computer as a human being
includes windows, icons, menus, pointers
interactive and intuititve
optimised for mouse and touch gesture
command line interface
text based
less source heavy compared to a GUI
more common than a GUI
efficient
useful for automating processing
menu driven interface
e.g. pin and chip devices
successive menus presented to the user
single options chosen at each stage
often with buttons on a keypad
natural language
responds to questions in spoken language
not always reliable
getting better all the time
multitasking
running multiple applications at the same time by giving each application a small slice off processor time
device drivers
translates operating system instructions into commands that the hardware will understand
The device can also pass data back to the operating system using the device driver
what is user mangement
allows different users to log into a computer
data from each user is saved, e.g. theme
users could have different access rights to files and programs
file management
data is stored in files
an extension to file name tells the operating system which application to load the file into
encryption
utilises use algorithms to scramble plain text into cypher text
defragmentation
reorganises files on a hard disk, putting fragments of files back together, and to collect free space
This reduces the movement of a read/write head across the surface of the disk speeding up file access
data compression
reduces the size of a file so that it takes up less space, and is quicker to download over the internet
System information utility
displays important data about the current state of the computer
e.g temperature
Diagnosis utility
detects and resolves items that are not working
e.g network connection
system software
Software that governs the computer system. It:
controls the hardware
allows applications to run
provides an interface for the user to interact with the computer
incremental backup
Only the changes made to the device needs to be backed up
Small number of files are used between backup
Take less time
Each backup will take less memory to store
full backup
backups all data, files and software
longer compared to incremental backup
faster to restore backups
open source software
The source code is distributed with the software
The customer can modify the source code
examples of utility system software
Defragmentation software
Backup software
Anti-virus
Firewall
why do solid state drives not need to be fragmented
Solid state drives do not need to be defragmented because they contain no moving parts
they are random access memory, not sequential access
Defragmenting an SSD actually reduces their lifespan
defragmentation requires a lot of read and write cycles, which SSDs have a finite amount of
functions of file management
copying files
deleting files
moving files
renaming files
what is peripheral management
allows external hardware to connect to the CPU
explain the process of defragmentation
files are moved around to create free space
file fragments are combined into the free space
files are all moved together, leaving all the free space in one place
difference between operating system and system software
operating system is essential for the function for the computer
system software is optional that can help the computer system
functions of the operating system
controlling hardware components
providing a platform for software to run on
providing a user interface
managing processes
managing the computer’s memory
fragmentation
When a file is stored as a series of segments
some segments run together in sequence and some are split up over a disk
paging
form of memory management
Memory is broken up into fixed-size blocks, known as pages
Process management
tasks related to processing like creation, scheduling, termination, deadlock, etc
multi-user operating system
Different users can log into the same computer, e.g, admins, school accounts.
allowing a personalised experience
what is a user interface
- human computer interaction
application software
used to carry out tasks on a computer, such as writing an email, making a poster, doing homework and messaging friends
