Operating Systems
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Transcript of Operating Systems
Operating Systems System Software, functions of an operating system
The Operating System The Operating System is also
known as System Software.
All computers must have an operating system in order to work
The OS is responsible for all the functions of hardware and also software
Functions of an Operating System
GUI
Device Drivers
Security Networking
Disk Management (File
Systems)
Memory Management
Process Management
Operating System
Process Management A multitasking OS allows the computer to
perform many different tasks(processes) at the same time
The CPU can only focus on one process at a time. The OS tells the CPU to give each process a very short time slice (time slot)
This happens very fast making it seem like the processes are occurring at the same time
Memory Management A computer has different memory
types it could use; memory registers, cache, RAM and disk storage.
The OS is responsible for checking; which memory if free which memory is to be allocated and de- allocated how to swap between the main memory and secondary memory
Memory Management When the OS swaps between main
memory and secondary memory we call this Virtual Memory management
Virtual memory creates a memory slot acting as RAM when the RAM is too full
Virtual memory is much slower than RAM
Disk Management / File SystemsOperating systems have different file
systems.
A file system is an organisation of all the files and folders saved within
the computer
Each OS has a different file system hence a different access system (notes page 29)
Networking Most of the OSs today are
capable of using the universal TCP/IP (Transmission Control Protocol/Internet Protocol)
This allows computers to communicate with each other and be able to share resources such as files and hardware devices over a network, such as Internet.
SecurityThe basic type of security an OS
offers is asking for a Username and Password before a user can use the OS
The OS could also limit certain users from doing certain actions. This is known as level access
The OS uses a Firewall to close certain ports when using TCP/IP protocol
GUI – Graphical User InterfaceMost operating systems use a GUI –
Graphical User interfaces, which is more user-friendly as it uses graphical representations which the user can easily understand.
A GUI's components are Icons, Menus, Windows, Toolbars , Buttons amongst others.
Windows GUI
Linux GUI
MAC GUI
Device Drivers A device driver is software that is
responsible for the communication between different hardware and the computer.
Device drivers are used to let the OS know how a specific hardware works as with all the new advances in technology it is impossible for the OS to know how ALL types of hardware work