PPSC PAST PAPERS OF COMPUTER ALL MCQS 2025(solved)

Are you preparing for the upcoming PPSC exams ? This post contains the most important and updated Computer Science MCQs with solved answers and short explanations. These MCQs are ideal for Lecturer Computer Science, IT Officers, Junior Computer Operators, and other PPSC technical posts.

We’ve carefully selected and rewritten these questions to match the latest PPSC syllabus and exam trends. From basic hardware and software concepts to internet protocols, programming, Excel, Windows, and security – this set covers everything you need to practice and revise effectively.

1. Which part of the computer is known as its brain?

• A) ALU
• B) Memory
• 🔵 C) CPU
• D) Central Unit

✔️ Correct Answer: C) CPU
🧠 Explanation: CPU (Central Processing Unit) controls all operations and processes instructions, so it’s considered the “brain” of the computer.

2. When a new Excel file is opened, how many sheets are available by default?

• A) 2
• 🔵 B) 3
• C) 4
• D) 5

✔️ Correct Answer: B) 3
🧠 Explanation: Older versions of Excel open with 3 default sheets, though this can be customized in settings.

3. Which shortcut key is used to insert a hyperlink in MS Office applications?

• A) Ctrl + S
• B) Ctrl + M
• 🔵 C) Ctrl + K
• D) None of the above

✔️ Correct Answer: C) Ctrl + K
🧠 Explanation: Ctrl + K is the universal shortcut in MS Word, Excel, and PowerPoint for inserting hyperlinks.

4. What is the primary function of Microsoft PowerPoint?

• 🔵 A) Presentation
• B) Drafting
• C) Worksheet
• D) All of these

✔️ Correct Answer: A) Presentation
🧠 Explanation: MS PowerPoint is mainly used for designing and presenting slide-based presentations.

5. In computing terms, what does PDF stand for?

• A) Print Document Format
• B) Portable Disc Format
• 🔵 C) Portable Document Format
• D) Portable Document Firewall

✔️ Correct Answer: C) Portable Document Format
🧠 Explanation: PDF is a universal format for fixed-layout documents that can be shared easily and look the same on all devices.

6. Which of these is an open-source operating system?

• A) UNIX
• B) Windows 2000
• C) Windows NT
• 🔵 D) Linux

✔️ Correct Answer: D) Linux
🧠 Explanation: Linux is an open-source OS that is free to use, distribute, and modify.

7. In PowerPoint, which key starts a slideshow from the current slide?

• A) F5
• B) Ctrl + F5
• 🔵 C) Shift + F5
• D) Alt + F5

✔️ Correct Answer: C) Shift + F5
🧠 Explanation: This shortcut is used when you want to start your slideshow from the currently selected slide.

8. Which function key is used to begin a PowerPoint slideshow from the start?

• A) F6
• B) F4
• 🔵 C) F5
• D) F3

✔️ Correct Answer: C) F5
🧠 Explanation: Pressing F5 in PowerPoint begins the slideshow from the first slide.

9. Which MS Office tool is designed to manage desktop databases?

• 🔵 A) MS Access
• B) MS PowerPoint
• C) MS Excel
• D) None of the above

✔️ Correct Answer: A) MS Access
🧠 Explanation: MS Access is a powerful database management tool included in the Office suite.

10. Vector graphics are made up of which of the following?

• 🔵 A) Paths
• B) Pixels
• C) Palette
• D) None of above

✔️ Correct Answer: A) Paths
🧠 Explanation: Unlike raster images, vector graphics are created using lines and curves called paths, making them scalable.

11. What is the shortcut key to create a new presentation in PowerPoint?

• A) Ctrl + N
• 🔵 B) Ctrl + Shift + N
• C) Ctrl + P
• D) Shift + N

✔️ Correct Answer: B) Ctrl + Shift + N
🧠 Explanation: Ctrl + Shift + N creates a new blank presentation in PowerPoint, depending on the version used.

12. The binary number system uses how many digits?

• A) 4
• B) 6
• 🔵 C) 2
• D) 1

✔️ Correct Answer: C) 2
🧠 Explanation: Binary uses only 2 digits: 0 and 1. It is the foundation of all computer operations.

13. What kind of printer uses a ribbon and impact mechanism?

• 🔵 A) Dot Matrix Printer
• B) Inkjet Printer
• C) Laser Printer
• D) Thermal Printer

✔️ Correct Answer: A) Dot Matrix Printer
🧠 Explanation: Dot Matrix printers work by physically striking the ribbon onto paper, producing characters.

14. In computing, the term ‘bit’ stands for what?

• 🔵 A) Binary Digit
• B) Bitrate
• C) Binary Tree
• D) Byte Information Type

✔️ Correct Answer: A) Binary Digit
🧠 Explanation: A bit is the smallest unit of data in computing and is short for “binary digit.”

15. Which memory is non-volatile and used to store firmware?

• A) RAM
• 🔵 B) ROM
• C) Cache
• D) Registers

✔️ Correct Answer: B) ROM
🧠 Explanation: ROM (Read-Only Memory) retains data permanently and stores essential programs like BIOS.

16. What is the function of an ALU in a computer?

• A) Stores data
• B) Controls input/output
• 🔵 C) Performs arithmetic and logic operations
• D) Transfers files

✔️ Correct Answer: C) Performs arithmetic and logic operations
🧠 Explanation: ALU (Arithmetic Logic Unit) is part of the CPU and is responsible for all mathematical and logical functions.

17. Which device is used to convert digital signals into analog signals?

• A) Switch
• 🔵 B) Modem
• C) Router
• D) Repeater

✔️ Correct Answer: B) Modem
🧠 Explanation: A modem modulates and demodulates signals between digital and analog forms, enabling internet access.

18. Which is an input device among the following?

• A) Monitor
• 🔵 B) Keyboard
• C) Printer
• D) Speaker

✔️ Correct Answer: B) Keyboard
🧠 Explanation: A keyboard is an input device used to type commands and data into the computer.

19. What type of memory loses its data when power is turned off?

• 🔵 A) RAM
• B) ROM
• C) SSD
• D) Flash

✔️ Correct Answer: A) RAM
🧠 Explanation: RAM (Random Access Memory) is volatile, meaning it stores data temporarily and loses it when power is lost.

20. Which one of these is a web browser?

• 🔵 A) Mozilla Firefox
• B) Windows
• C) Linux
• D) Google Docs

✔️ Correct Answer: A) Mozilla Firefox
🧠 Explanation: Firefox is an open-source web browser used to access websites and online content.

21. Which of the following is considered secondary storage?

• A) RAM
• 🔵 B) Hard Disk
• C) Cache
• D) Register

✔️ Correct Answer: B) Hard Disk
🧠 Explanation: Hard disks store data permanently and are part of secondary memory — unlike RAM which is primary memory.

22. In Excel, the formula bar shows what?

• A) Row number
• 🔵 B) Cell contents or formulas
• C) Cell format
• D) Sheet title

✔️ Correct Answer: B) Cell contents or formulas
🧠 Explanation: The formula bar displays what is entered or calculated in a selected Excel cell.

23. Which computer component holds temporary data currently being processed?

• A) Hard Drive
• 🔵 B) RAM
• C) USB
• D) CD-ROM

✔️ Correct Answer: B) RAM
🧠 Explanation: RAM stores data temporarily while programs are running, making access fast for processing.

24. What does HTTP stand for?

• A) Hyper Terminal Text Protocol
• 🔵 B) Hypertext Transfer Protocol
• C) High Tech Text Program
• D) Hosting Transfer Text Platform

✔️ Correct Answer: B) Hypertext Transfer Protocol
🧠 Explanation: HTTP is the foundation protocol used for transferring web pages on the internet.

25. What is the purpose of an operating system?

• A) Writing programs
• 🔵 B) Managing hardware and software resources
• C) Browsing websites
• D) Designing databases

✔️ Correct Answer: B) Managing hardware and software resources
🧠 Explanation: An OS handles all the core tasks such as memory management, file handling, and hardware interaction.

26. Which device connects multiple computers in a network?

• A) CPU
• 🔵 B) Switch
• C) Scanner
• D) Modem

✔️ Correct Answer: B) Switch
🧠 Explanation: A switch links computers within a local network, allowing them to communicate and share data.

27. Which device is used to scan hard copy images into a computer?

• A) Printer
• 🔵 B) Scanner
• C) Monitor
• D) Speaker

✔️ Correct Answer: B) Scanner
🧠 Explanation: A scanner converts paper documents or photos into digital format for computer storage and editing.

28. What unit is used to measure processor speed?

• A) Byte
• 🔵 B) Hertz
• C) Bit
• D) Pixel

✔️ Correct Answer: B) Hertz
🧠 Explanation: Processor speed is measured in hertz (Hz), usually gigahertz (GHz), indicating clock cycles per second.

29. Which key is used to rename a file or folder in Windows?

• A) F4
• B) F3
• 🔵 C) F2
• D) F5

✔️ Correct Answer: C) F2
🧠 Explanation: In Windows OS, pressing F2 allows you to rename selected files or folders quickly.

30. Which storage device is portable and uses flash memory?

• A) Hard disk
• 🔵 B) USB Flash Drive
• C) CD-ROM
• D) RAM

✔️ Correct Answer: B) USB Flash Drive
🧠 Explanation: USB drives are portable, use flash memory, and are commonly used to store or transfer files.

31. Which one of these is an example of application software?

• A) BIOS
• B) Device Driver
• 🔵 C) MS Word
• D) Cache

✔️ Correct Answer: C) MS Word
🧠 Explanation: MS Word is an application program used for word processing — unlike system-level software like BIOS or drivers.

32. What part of a computer temporarily stores data for quick access?

• 🔵 A) Cache
• B) ROM
• C) USB
• D) Motherboard

✔️ Correct Answer: A) Cache
🧠 Explanation: Cache memory is small but very fast memory used to store frequently accessed data near the CPU.

33. In Excel, which symbol is used to start a formula?

• A) $
• 🔵 B) =
• C) #
• D) &

✔️ Correct Answer: B) =
🧠 Explanation: All formulas in Excel start with an equals sign (=), indicating calculation or logic.

34. Which file extension is used for MS Word documents?

• A) .xls
• 🔵 B) .docx
• C) .pptx
• D) .txt

✔️ Correct Answer: B) .docx
🧠 Explanation: .docx is the standard file extension for Microsoft Word documents (from 2007 onwards).

35. Which programming language is primarily used for web development?

• A) C++
• B) Python
• 🔵 C) HTML
• D) Java

✔️ Correct Answer: C) HTML
🧠 Explanation: HTML (Hypertext Markup Language) is the base language used for creating web pages and content layout.

36. What is the process of starting or restarting a computer called?

• 🔵 A) Booting
• B) Logging in
• C) Formatting
• D) Processing

✔️ Correct Answer: A) Booting
🧠 Explanation: Booting is the initial process where the operating system loads into memory after powering on.

37. Which key combination is used to copy selected text or files?

• A) Ctrl + X
• 🔵 B) Ctrl + C
• C) Ctrl + V
• D) Ctrl + Z

✔️ Correct Answer: B) Ctrl + C
🧠 Explanation: Ctrl + C is the universal shortcut key for copying data to clipboard.

38. Which key is commonly used to refresh a webpage or window?

• 🔵 A) F5
• B) F2
• C) F9
• D) F1

✔️ Correct Answer: A) F5
🧠 Explanation: Pressing F5 refreshes the current webpage or window in browsers and many applications.

39. Which of the following is a pointing device?

• A) Keyboard
• B) Monitor
• 🔵 C) Mouse
• D) Printer

✔️ Correct Answer: C) Mouse
🧠 Explanation: A mouse is a pointing device used to control the cursor and select items on screen.

40. What does GUI stand for?

• A) Global User Information
• 🔵 B) Graphical User Interface
• C) General User Interaction
• D) Graphic Utility Indicator

✔️ Correct Answer: B) Graphical User Interface
🧠 Explanation: GUI refers to a user-friendly interface that uses visuals like windows, icons, and menus to interact with the system.

41. Which programming language is considered the foundation of modern programming?

• A) Python
• 🔵 B) C
• C) HTML
• D) PHP

✔️ Correct Answer: B) C
🧠 Explanation: C language is known as the mother of all modern languages like C++, Java, etc., due to its structure and influence.

42. What does the abbreviation ‘URL’ stand for?

• A) Uniform Resource Link
• 🔵 B) Uniform Resource Locator
• C) Unique Resource Locator
• D) Uniform Registered Link

✔️ Correct Answer: B) Uniform Resource Locator
🧠 Explanation: A URL is the address used to access resources on the internet, such as websites.

43. In Excel, what is the default file extension for saved spreadsheets?

• A) .docx
• B) .pptx
• 🔵 C) .xlsx
• D) .xlsm

✔️ Correct Answer: C) .xlsx
🧠 Explanation: Modern versions of MS Excel save files using the .xlsx extension, indicating a workbook.

44. Which of the following is not a programming language?

• A) Python
• 🔵 B) HTTP
• C) Java
• D) C++

✔️ Correct Answer: B) HTTP
🧠 Explanation: HTTP is a protocol used for web communication, not a programming language.

45. Which technology is used to make calls over the Internet?

• A) GSM
• 🔵 B) VoIP
• C) LTE
• D) USB

✔️ Correct Answer: B) VoIP
🧠 Explanation: VoIP (Voice over Internet Protocol) enables voice communication via internet services like Skype and WhatsApp.

46. Which of the following is the largest unit of digital data?

• A) Megabyte
• B) Gigabyte
• 🔵 C) Terabyte
• D) Kilobyte

✔️ Correct Answer: C) Terabyte
🧠 Explanation: 1 Terabyte = 1024 Gigabytes; it is one of the largest commonly used data measurement units.

47. What is the purpose of a firewall in a computer system?

• A) Cool the system
• 🔵 B) Protect from unauthorized access
• C) Monitor internet speed
• D) Delete viruses

✔️ Correct Answer: B) Protect from unauthorized access
🧠 Explanation: A firewall acts as a security barrier that filters incoming and outgoing network traffic.

48. Which key combination is used to paste copied content?

• A) Ctrl + X
• 🔵 B) Ctrl + V
• C) Ctrl + P
• D) Ctrl + A

✔️ Correct Answer: B) Ctrl + V
🧠 Explanation: Ctrl + V pastes content from the clipboard into your document or program.

49. Which software helps to detect and remove computer viruses?

• A) Driver
• 🔵 B) Antivirus
• C) Notepad
• D) Compiler

✔️ Correct Answer: B) Antivirus
🧠 Explanation: Antivirus software scans and removes malicious software to keep systems secure.

50. Which symbol is used in programming for ‘OR’ operation?

• A) &&
• B) ==
• 🔵 C) ||
• D) %%

✔️ Correct Answer: C) ||
🧠 Explanation: In many programming languages like C, Java, || represents the logical OR operator.

51. Which of these is an example of an operating system?

• 🔵 A) Windows
• B) Chrome
• C) Intel
• D) Google

✔️ Correct Answer: A) Windows
🧠 Explanation: Windows is a widely used operating system developed by Microsoft for personal computers.

52. What does IP stand for in networking?

• A) Internet Power
• 🔵 B) Internet Protocol
• C) Internal Program
• D) Internet Provider

✔️ Correct Answer: B) Internet Protocol
🧠 Explanation: IP (Internet Protocol) is a set of rules for addressing and routing data across the internet.

53. Which device is used to input sound into a computer?

• A) Speaker
• 🔵 B) Microphone
• C) Monitor
• D) Modem

✔️ Correct Answer: B) Microphone
🧠 Explanation: A microphone is an input device that captures audio for voice recording or calls.

54. Which type of file is typically used for audio storage?

• 🔵 A) .mp3
• B) .docx
• C) .xlsx
• D) .exe

✔️ Correct Answer: A) .mp3
🧠 Explanation: The .mp3 extension is used for audio files and is one of the most common music file formats.

55. Which key is used to permanently delete a file without moving it to the Recycle Bin?

• A) Ctrl + D
• 🔵 B) Shift + Delete
• C) Alt + Delete
• D) Ctrl + Shift

✔️ Correct Answer: B) Shift + Delete
🧠 Explanation: When you use Shift + Delete, the file bypasses the Recycle Bin and is deleted permanently.