All Free Computer Science and IT MCQs with Answers

201. Who invented Slide Rules?

• A. John Napier
• B. William Oughtred
• C. Gottfried Leibnitz
• D. Blaise Pascal

Explanation: William Oughtred invented the slide rule by developing a calculating instrument based on logarithmic scales. John Napier invented logarithms, which made the slide rule possible, but not the slide rule itself.

202. Serial access memories are useful in applications where:

• A. Data consists of numbers
• B. Short access time is required
• C. Each stored word is processed differently
• D. Data naturally needs to flow in and out in serial form

Explanation: Serial-access memory is suitable when information naturally enters and leaves one bit or word after another in sequence. It is not preferred when each word needs rapid independent access.

203. Identify the true statement about computer.

• A. Computers are 100% accurate but it can suffer from GIGO (Garbage In Garbage Out)
• B. Computers are reliable because they use electronic component which have very low failure rate
• C. Computer is never tired and does not suffer from boredom
• D. All of above

Explanation: All three statements describe standard computer characteristics: electronic components make computers reliable, they do not get tired, and their accuracy depends on correct input because of GIGO. Therefore, all of the listed statements are true.

204. The CPU comprises of Control, Memory and_______________units?

• A. Microprocessor
• B. Arithmetic/Logic
• C. Output
• D. ROM

Explanation: The CPU is commonly described as containing the control unit, memory unit, and arithmetic/logic unit. The ALU performs calculations and logical comparisons, while the control unit directs operations.

205. Which of the following uses a handheld operating system?

• A. supercomputer
• B. personal computer
• C. Laptop
• D. PDA

Explanation: A PDA, or personal digital assistant, is a handheld computing device and therefore uses a handheld operating system. Supercomputers, PCs, and laptops are not normally classified as handheld devices.

206. C' in CPU denotes___________?

• A. Central
• B. Common
• C. Convenient
• D. Computer
• E. None of these

Explanation: In CPU, the letter C stands for Central, giving the term Central Processing Unit. The name describes the unit that centrally executes and controls computer instructions.

207. In which type of computer, data are represented as discrete signals?

• A. Analog computer
• B. Digital computer
• C. both
• D. Hybrid Computer

Explanation: Digital computers represent data using discrete values, most commonly binary 0s and 1s. Analog computers work with continuously varying signals, while hybrid computers combine both approaches.

208. In world today, most of the computers are_____________?

• A. Digital
• B. Hybrid
• C. Analog
• D. Complex

Explanation: Most computers in use today are digital because digital systems provide reliable storage, processing, and transmission using discrete binary values. Analog and hybrid computers serve more specialized purposes.

209. Computers, combine both measuring and counting, are called________________?

• A. Analog
• B. Digital
• C. Hybrid
• D. All of these

Explanation: Hybrid computers combine analog measurement with digital counting and processing. This allows them to handle both continuously varying quantities and discrete numerical data.

210. Note book, laptop,palm,hand-held computers are coming under the category of__________computer?

• A. Digital computer
• B. Mainframe computer
• C. Portable computer
• D. Hybrid computer

Explanation: Notebooks, laptops, palmtops, and handheld systems are classified as portable computers because they can be carried and operated away from a fixed desk. Digital and hybrid describe processing methods, not portability.