All Free Computer Science and IT MCQs with Answers

181. BCD stands for

• A. Bit Coded Decimal
• B. Binary Coded Digit
• C. Bit Coded Digit
• D. Binary Coded Decimal

Explanation: BCD means Binary Coded Decimal, a representation in which each decimal digit is encoded separately using binary bits. It is different from ordinary binary, which encodes the entire number as one value.

182. The arranging of data in a logical sequence is called ____________.

• A. Classifying
• B. Sorting
• C. Summarizing
• D. Reproducing

Explanation: Sorting arranges data according to a logical order, such as alphabetical, numerical or chronological order. Classifying groups data into categories, while summarizing reduces it to key points.

183. When was the first electro-mechanic Computer developed?

• A. 1880
• B. 1944
• C. 1960
• D. 1980

Explanation: The Harvard Mark I, completed in 1944, is commonly identified as the first large electromechanical computer. It used electrically controlled mechanical components rather than fully electronic switching.

184. _____ computers are also called personal computers.

• A. Super Computers
• B. Mini Computers
• C. Micro Computers
• D. Mainframe Computers

Explanation: Microcomputers use a microprocessor as their central processing unit and include personal computers. Mainframes, minicomputers and supercomputers are larger computer categories.

185. Which of the following is the largest storage?

• A. Megabyte
• B. Petabyte
• C. Kilobyte
• D. Terabyte
• E. Gigabyte

Explanation: Petabyte is larger than terabyte, gigabyte, megabyte, and kilobyte. In the usual decimal order, storage units increase as KB, MB, GB, TB, then PB.

186. Bit is also called ______________.

• A. Small
• B. Character
• C. Byte
• D. Binary Digit

Explanation: Bit is short for binary digit, and it can hold one of two values, 0 or 1. A byte contains eight bits, so byte and bit are not interchangeable.

187. Components of computer system are?

• A. Hardware
• B. Software
• C. Applications
• D. Both A and B

Explanation: A computer system fundamentally consists of hardware, the physical equipment, and software, the instructions that operate it. Applications are a category of software, so “both A and B” is the inclusive answer.

188. A device through which we enter data in a computer known as ___________?

• A. Storage Device
• B. Internal Device
• C. Prcessing Device
• D. Input Device

Explanation: An input device enters data or commands into a computer, such as a keyboard, mouse, or scanner. Storage and processing devices perform different functions after or around the input stage.

189. Digital computer was invented by?

• A. John Vincent Atanasoff
• B. Steve Jobs
• C. Charless babbage
• D. James watson

Explanation: John Vincent Atanasoff helped build the Atanasoff-Berry Computer, commonly regarded as an early electronic digital computer. Charles Babbage designed an earlier mechanical calculating machine, while the other names are unrelated.

190. In computer, ALU has____________?

• A. 2units
• B. 3units
• C. 4units
• D. 5units

Explanation: The ALU has two fundamental sections: the arithmetic unit performs calculations, while the logic unit performs comparisons and logical operations. These are commonly described as the two units of the ALU.