Operating System

Operating System

1. Multitasking

   • Multitasking allows the PC to run faster as more commands and programs are being processed at once
   • If the OS didn't multitask, then only one program would run at once until it was closed, then the next program would run

2. The user interface

   • How does the user interact with the Operating System?
     • Command Line Interface
       • Text Based
         • E.g DOS, Raspian (for Raspberry Pi)
     • Graphical User Interface
       • Contains Windows, Icons, Menus, Pointers (Visual)
         • E.g. Windows 10, Windows 8, Android, Mac OS

3. Memory Management

   • The OS allocates memory between the different programs that are open at the same time
   • Programmers and users do not need to know where in memory data is being held – it is the purpose of the Operating System to do this
   • A piece of software called "The Kernel" allows programs to run at the same time, and allows the data to communicate to the OS, as a sort of bridge
     • Applications
       • Kernel
         • CPU
         • Memory
         • Devices

4. Drivers

   • Drivers are a piece of software used to control another piece of software
   • Allow a peripheral device to be connected to a computer and it be used by the operating system

5. Peripherals Managment

   • Operating systems manage the way in which hardware interacts with software
   • A peripheral is a piece of hardware that is not directly connected to the CPU (A Keyboard, Mouse, even a Hard Drive)
   • An Operating System manages all of the peripheral devices that are connected to the computer - This allows them to be disabled, or drivers be updated

6. File management

   • Like memory management, the Operating System must identify where files are stored for long term storage (On a HDD, or SSD for example)
   • The user does not need to know the specific track, sector and surface address – but the Operating System does in order to accurately locate a file on the hard disk drive.