Operating Systems

Operating Systems

1. Systems software: operating systems and utility software.

   • System software is software that manages the computer.
   • Application software is software that does something useful for the users.

2. Operating system the mist important piece of software on any computer.

   • Without the operating system, no programs will run.
   • Responsible for controlling/ communicating with the hardware.
   • Provides a platform for games, browsers, music players etc to work on.
   • Interface between user and hardware.
   • Hides complexities of hardware from user.
   • User doesn't need to know exactly where files are stored on hard disk drive, operating systems do everything for users.
   • Sits between the user's applications and hardware.
   • Enables applications to use hardware resources.
   • 6 main functions.

3. User interface- enables a person to interact with a computer.

   • Graphical user interface/ command line interface.
   • GUI: uses graphics, icons and menus.
   • CLI: used by people with tech knowledge, very quick, often used by system administrators.
   • Menu drive interface: menus to control computers. E.G. Card machines, MP3 Players.
   • Natural language interface: Siri, Cortnana, Alexa.

4. Kernel in centre of operating system. Processor scheduling, memory management.

5. Multitasking: gives processor time slice for each task, appears to be doing things at same time, but it isn't.

6. Memory management allocates memory between different programs, puts everything in its own place.

   • Memory management moves programs between RAM and virtual memory.

7. Peripheral devices: any hardware not directly connected to the CPU.

   • Device drivers allow peripherals to be connected to a computer for OS to use it.