Computer Operating System Questions and Answers

Answer: D

The one that is not an operating system is Opera.

Opera is a web browser, like Chrome, Firefox and Edge.

The other three are operating systems: Linux is a family of open-source operating systems built on the Linux kernel, Ubuntu is one of the most popular Linux distributions, and Android is Google's Linux-based operating system for phones and tablets.

Answer: D

iPhone OS (now iOS) is not Linux based. It was developed by Apple and derives from its own Unix-like Darwin and Mac OS X code, not from the Linux kernel. Android is built on a modified Linux kernel, and WebOS (originally from Palm, later HP and LG) and Maemo (from Nokia) are also Linux-based mobile platforms.

Answer: D

The feature is multitasking.

A multitasking operating system lets more than one program (task) run concurrently on the same computer. The processor switches rapidly between tasks, giving each a short slice of time, so a user can, for example, type a document while music plays and a file downloads.

Multi user means several users can use the system at the same time, which is about users, not programs. Multiprocessing means the computer has more than one processor, which is hardware rather than the ability to run several programs. A switching system is a telecommunication term.

Answer: C

Unix is known for a command-based interface.

Users work with Unix through a shell, typing commands at a prompt (for example ls, cp, grep) and combining them with pipes. This command-line interface is the classic way of using Unix and its descendants.

Graphical desktops can be added on top of Unix (such as the X Window System), but they are not its defining interface. Voice-based and touch-based interfaces belong to smart assistants and mobile devices.

Answer: B

The central part of UNIX is the Kernel.

The kernel is the core of the operating system: it manages memory, processes, devices and the file system, and runs in privileged mode. Everything else talks to the hardware through it.

The shell is the command interpreter that users interact with, which sits outside the kernel; directories, programs and files are what the system manages, not its central part.

Answer: C

The answer is Virtual memory.

Virtual memory lets the operating system use part of the disk as an extension of RAM. Programs are divided into pages, and only the pages in use are kept in physical memory, so a program larger than the installed RAM can still run.

Job scheduling decides the order in which jobs get the processor. Time sharing gives several users slices of CPU time. Neither increases the memory a program can use. 'Multi sharing' is not a standard memory-management technique.

Answer: A

System utilities exist to perform maintenance and configuration tasks.

Utility programs are system software that keep the computer in good order: disk cleanup and defragmentation, antivirus scanning, backup, file compression and device configuration are typical examples.

Writing code is done with editors and compilers, which are programming tools. Running application software is the job of the operating system, which loads and schedules programs. Operating the complete hardware is also the operating system's role, through its kernel and drivers, not that of a utility.

Answer: C

A program in execution is called a process.

A program is a passive set of instructions stored on disk. When it is loaded into memory and run, the operating system creates a process for it, with its own program counter, registers, memory space and state such as ready, running or waiting.

Data is the information a program works on. 'System' is too general a term, covering the whole computer or its software. A cycle, such as the instruction or machine cycle, is one step of the processor's work, not a running program.

Answer: C

Correct answer: Real time system

A real-time system must respond within a deadline set by the process it controls, because a correct answer that arrives late is useless - the world has moved on. Batch and time-sharing systems aim at throughput and fair response instead, with no guaranteed deadline.

Answer: B

Correct answer: Public domain program

A public domain program carries no copyright restriction, so anyone may compile, use, change and redistribute it freely. Shareware is copyrighted and may be tried before purchase but must then be paid for, and firmware describes where a program is stored rather than its licence.