Systems Software Flashcards
Whats an operating system
A software which manages hardware and software resources and provides an interface for the uswr
Whats utility system
Helps maintain and support the computer such as a disc cleaner, backup software, antivirus software
Whats a kernel
The heart and core of an operating system which manages operations of computers and hardware
Whats a shell
An environment or a special user program which provides an interface to user
Whats the CPU?
The brain of the computer manages applications and software
Whats the bootstrap loader
A program wich starts up the OS when a computer is turned on
Where is the bootstrap loader found
In the ROM (read only memory) because its non volatile
Whats the purpose of the RAM?
Holds data and instructions currently in use
What are the peripheral devices
The input and output devices like a printer, keyboard, mouse
The 5 purposes of OS
• provide user interface
• memory managment
• Multitasking
• peripheral managmenet
• user management
Where can you access the operating system
The C drive
Memory management in OS
the OS manages RAM
When you open an application
The OS will copy it onto the RAM
the OS makes sure each program has its own space so they dont overwrite each others data.
What is peripheral management
The OS manages the input and output devices of the computee
What is the user interface
Means coming together
Provides users with an interface so they can interact wih a computer
Whats the 3 types of interface
GUI (graphical user interface)
Menu driven interface
Command line interface
Whats the GUI?
Uses windows, menus and pointers to control the computer
Mid 80s
Windows and mac
Whats the menu driven interface
Uses menus to control the computer
Uses icons and windows to represent applications
Mobile phones
Mp3 players (if not on menu you cant do it)
Whats the command line interface
Written commands control computers
The only way back then to communicate with a computer
Only linux use it now
How does the CPU multitasking
OS enables multitasking by managing the CPUs processes
Many programs can now run at the same time
OS allows each program to take turns or getting the shortest job done firet
Whats user management
Ensure users data is not seen by anyone using username and password.
Give users different permissions
What access rights might a file manager track
• read
• modify
• execute
The role of file managing
Responsible for keeping track of where specific files are located and determining the type of file. Also determines the access rights of each file
Responsibilities of user manager
• handles authentication
• making decision based on access rights
• keeping track of who is logged in
Why do user managers need to keep track of whos logged in?
A line of defense against security breaches and also if someone were to forget to log out.
Whats encryption
The scrambling of data to protect sensitive data
Whats defragmentation
A type of utility software which reorganises data in different blocks by consolidating files on your hard drive and increases performance of computer
Whats fragmentation
When a single file is stored in different places on a storage device its fragmented (also takes longer to load up)
Why should SSD’s never be defragmented
• they provide random access to data
• defragmenting it will push the device towards its read/ write cycle limit which shortens its lifetime
4 types of utility software
• backup
• compression
• defragmentation
• encryption
What are two types of backup
• full
• incremental
Why is memory management important
• allows programs to allocate memory
• makes sure programs dont overwrite each others data
• allows large programs to run
Whats segmentation
Shortest job first
Whats real time
The OS gives a response with a guaranteed time frame
Whats paging
When memory is split up into equal sized sections aka pages.
Whats virtual memory
It uses a section of the hard drive to act as RAM when the space in main memory is insufficient to store programs’ data.
The sections of programs are temporarily moved through paging which frees memory for programs in RAM.
Pros and cons for shortest job first
Pro: waiting time reduced
Cons: requires processor to calculate time for each job, doesnt take into account job priority or urgency
Advantage and disadvantage of first come first serve
Pro: straightforward to implement
Con: job priority, urgency not considered
Whats round robin?
Each job is given a time slice- within which its allowed to execute. The process is repeated until job complete,
Pro: all jobs soon attended to
Con: longer jobs longer time
Job priority not considered
Whats an embedded system
A computer system with a function built within a larger mechanical device. Its purpose is to control the device and allow a user to interact with it.
