A3 - Operating Systems

A3 - Operating Systems

1. Types of operating systems

   • Single user, multi tasking
     • This is the type of operating system which runs on a standalone PC or laptop. The Windows operating system for example, can run many jobs simultaneously, switching rapidly between them so that each one appears to be the only one running.
   • Single user, single tasking
     • In the early days of PCs, and on early mobile phones, this was the only type of operating system (OS) available. The OS could only load and run one program at a time. The OS typically has a menu interface for the user to select setting, buttons and controls to operate the camera.

2. What is an operating system?

   • What is an operating system? An operating system is a program or set of programs that manages the operations of the computer for the user.
     • The operating system enables the user to complete all their various tasks such as loading and running programs or apps, saving or printing files. It provides a simple interface to enable the user to give instructions.

3. Role of the operating system

   • Managing networks
     • A network operating system (OS) may be based on a client-server network in which a server enables multiple clients to share resources. Programs and data may be held in a dedicated file server, enabling all client devices connected to the network to share resources
   • Security
     • Access to a computer, whether standalone or on a network. A user will normally have to be authenticated by typing in a password or PIN, or by biometric identification, before they can use the device.

4. Devise drivers

   • A device driver is a computer program that provides software for a particular hardware device. It enables OS to access hardware functions without needing to know details of the hardware being used.

5. Real-Time operating system

   • A real-time operating system is used in applications that need to respond to data input within a fraction of a second.
     • It must respond very quickly to any inputs or sensors It must be able to deal with many inputs simultaneously
     • It must be able to deal with many inputs simultaneously