Introduction to OS, Its Roles & Types Video Lecture | Question Bank for GATE Computer Science Engineering - Computer Science Engineering (CSE)

Ans. An operating system (OS) is a software that manages computer hardware and software resources and provides common services for computer programs. Its main roles include managing computer memory, allocating system resources, controlling input and output devices, facilitating communication between software and hardware components, and providing a user interface for interaction with the computer system.

Ans. There are several types of operating systems, including: - Single-user, single-tasking: These operating systems, such as MS-DOS, can handle only one user and one task at a time. - Single-user, multi-tasking: Examples of such operating systems are Windows and macOS, which allow multiple applications to run simultaneously but still have a single user. - Multi-user: Operating systems like Linux and UNIX can support multiple users simultaneously, with each user having their own separate environment. - Real-time: Real-time operating systems, like QNX, are designed to quickly respond to events and process data in real-time, commonly used in critical systems such as aircraft control. - Distributed: Distributed operating systems, such as Google's Android, enable multiple machines to work together as a single system, sharing resources and coordinating tasks.

Ans. The operating system manages computer memory by allocating and deallocating memory space to different programs and processes. It keeps track of which parts of memory are in use and which parts are available. When a program or process needs memory, the operating system finds a suitable block of memory and assigns it to the program. It also ensures that each program or process is isolated from accessing memory assigned to other programs, providing memory protection.

Ans. The operating system plays a crucial role in controlling input and output devices. It provides device drivers, which are software modules that allow the operating system to communicate with specific hardware devices. The device drivers handle the details of how to interact with the devices, such as sending commands and receiving data. The operating system also manages input/output requests from different programs, ensuring that multiple programs can share the same input/output devices without conflicts.

Ans. The operating system provides a user interface (UI) for users to interact with the computer system. There are two main types of user interfaces: command-line interface (CLI) and graphical user interface (GUI). In a CLI, users interact with the computer by typing commands into a text-based interface. Examples include the Windows Command Prompt and Unix/Linux terminals. In a GUI, users interact with the computer through graphical elements like icons, windows, and menus. Examples include Windows, macOS, and Linux desktop environments. The operating system manages the UI components, processes user input, and displays output accordingly.