Computer Science MCQs – Page 1 (Q1-10)

A computer is correctly defined as an electronic device that processes data according to a set of instructions, distinguishing it from simple electrical appliances that perform only one fixed task. This input-process-output cycle is the foundation of all computing, whether in a smartphone, a laptop, or a supercomputer. The instructions a computer follows are called software or programs, while the physical parts (screen, processor, keyboard) are hardware. Because computers can be reprogrammed to do different jobs, they are considered general-purpose machines, unlike a calculator or a washing machine which are built for a single purpose.

The basic function of any computer is captured by the Input-Process-Output cycle: data enters through input devices, the CPU processes it according to instructions, and results are delivered as output. This model, sometimes extended to include storage as a fourth stage, underlies every computing task from typing a document to running complex simulations. Input devices include the keyboard and mouse, while output devices include monitors and printers. Understanding this cycle helps explain why a computer needs both hardware to carry out the steps and software to direct what happens at each stage.

Charles Babbage is widely credited as the father of the modern computer because he designed the Analytical Engine, a mechanical general-purpose computing device conceived in the 1830s that included many concepts found in today’s computers, such as a processing unit and memory. Although it was never fully built in his lifetime due to the engineering limits of the era, his design anticipated the stored-program concept later realized by John von Neumann. Babbage worked closely with Ada Lovelace, who wrote programs for the Analytical Engine and is regarded as the first computer programmer. His vision laid the conceptual groundwork for the computing revolution over a century later.

Charles Babbage is famous for designing the Analytical Engine, a proposed mechanical general-purpose computer that could be programmed using punched cards, an idea borrowed from the Jacquard loom. It featured components resembling a modern CPU’s arithmetic unit and memory store, making it a genuine conceptual ancestor of today’s computers. Babbage never completed a working model because Victorian-era manufacturing could not produce the precise parts required. Ada Lovelace wrote algorithms for the machine, including one considered the first computer program, earning her the title of the first programmer.

Ada Lovelace is regarded as the world’s first computer programmer because she wrote a detailed algorithm intended to be processed by Charles Babbage’s Analytical Engine, making it the first published computer program. She also foresaw that computers could go beyond pure number-crunching to manipulate symbols and even create music or art, an idea remarkably ahead of her time. Lovelace was the daughter of poet Lord Byron and collaborated closely with Babbage in the 1840s. In her honor, the U.S. Department of Defense named a programming language ‘Ada’ in 1980.

ENIAC correctly stands for Electronic Numerical Integrator and Computer, one of the earliest general-purpose electronic digital computers, completed in 1945. It used thousands of vacuum tubes, weighed about 30 tons, and occupied a large room, yet it could perform calculations far faster than earlier mechanical or electromechanical machines. ENIAC was originally built to calculate artillery firing tables for the U.S. military but was later used for a broader range of scientific problems. It exemplifies first-generation computing technology, which relied on vacuum tubes before transistors made computers smaller and more reliable.

ENIAC was built in the United States, developed at the University of Pennsylvania’s Moore School of Electrical Engineering and completed in 1945. It was funded by the U.S. Army to compute artillery trajectories during World War II, reflecting how early computing was closely tied to military research. The project involved key figures such as John Mauchly and J. Presper Eckert, and its programming was carried out largely by a team of women who are now recognized as pioneering computer programmers. ENIAC’s success helped spur the development of subsequent stored-program computers like EDVAC.

A computer’s ability to perform tasks by following a set of instructions is called a program, or more broadly, software. Software is distinct from hardware, which refers to the physical components like the CPU, memory, and monitor. Programs range from simple scripts to complex operating systems and applications, and they are typically written in programming languages before being translated into machine code the CPU can execute. This separation of hardware and software is what allows the same physical computer to run word processors, games, or accounting systems simply by loading different programs.

Software, also called a program, is the correct term for a set of instructions that tells a computer what to do, in contrast to hardware, which is the physical equipment. Software is generally divided into system software, like operating systems that manage the computer itself, and application software, like word processors and browsers that perform user tasks. Programs are written by developers in programming languages such as Python or C++, then compiled or interpreted into instructions the CPU can execute. Without software, computer hardware would be inert and unable to perform any useful function.

Emotion or feelings is correctly identified as not a characteristic of a computer, since computers lack consciousness, intuition, and genuine emotional understanding despite exhibiting apparent ‘intelligence’ in some tasks. True computer characteristics include speed, accuracy, diligence, storage capacity, and versatility, all of which stem from following precise electronic instructions rather than judgment or feeling. This lack of emotion means computers cannot get bored, tired, or biased in the human sense, though software can still contain errors or reflect biases introduced by their human programmers or training data. This distinction is fundamental to understanding the difference between human and artificial intelligence.