Basics of Computers and Generations: Parts, Memory and MCQs

The correct answer is B, Charles Babbage. He designed the Difference Engine and then the Analytical Engine, and the Analytical Engine contained the logical parts of a modern computer: a store for holding numbers, a mill for calculating, punched-card input and a printed output. He never finished building it, but the design is the reason he carries the title.

Option A, Blaise Pascal, built the Pascaline in 1642, the first mechanical adding machine, so he belongs to the earlier age of calculators rather than computers. Option C, Alan Turing, gave the theory of computation and the Turing machine and is called the father of computer science and of artificial intelligence, which is a different title from the one asked here. Option D, Herman Hollerith, built the punched-card tabulating machine used for the American census and founded the firm that later became IBM. Examiners rotate these four names in the options, so fix one phrase to each.

The correct answer is A, the first generation. Machines such as ENIAC, EDVAC and UNIVAC-I ran on thousands of vacuum tubes, which made them enormous, power-hungry and dependent on constant cooling. They were programmed in machine language and used punched cards for input and magnetic drums for storage.

Option B, the second generation, replaced the tube with the transistor invented at Bell Laboratories in 1947, which cut the size and heat sharply and allowed assembly language and the first high-level languages such as COBOL and FORTRAN. Option C, the third generation, is defined by the integrated circuit demonstrated by Jack Kilby in 1958, and brought the keyboard, the monitor and the operating system. Option D, the fourth generation, begins with the microprocessor and very large scale integration, the Intel 4004 of 1971 being the first commercial one. Learn the chain tube, transistor, integrated circuit, microprocessor in order.

The correct answer is C, Bell Laboratories. John Bardeen, Walter Brattain and William Shockley demonstrated the transistor there in 1947, and the three shared the Nobel Prize in Physics for it. Because a transistor did the work of a vacuum tube while being far smaller, cooler and more reliable, it became the defining component of the second generation of computers.

Option A, Texas Instruments, is where Jack Kilby built the first integrated circuit in 1958, which belongs to the third generation, so it is the classic trap in this question. Option B, Intel Corporation, was founded much later and released the Intel 4004 microprocessor in 1971, opening the fourth generation. Option D, IBM Research, produced important second and third generation machines such as the IBM 1401 and the System 360, but it did not invent the transistor. Keep the pairs fixed: transistor with Bell Labs, integrated circuit with Texas Instruments, microprocessor with Intel.

The correct answer is D, UNIVAC-I, the Universal Automatic Computer. It was the first electronic computer built to be sold to customers rather than used only in a laboratory, and it was famously put to work on census and business data processing. It belongs to the first generation and used vacuum tubes.

Option A, ENIAC, the Electronic Numerical Integrator and Computer, was built by J. Presper Eckert and John Mauchly and is remembered as one of the first general-purpose electronic computers, but it was a one-off machine and not a commercial product. Option B, EDVAC, was its successor and is remembered for putting the stored program idea into practice. Option C, the Harvard Mark I, was an electro-mechanical machine driven by relays rather than a fully electronic computer. Papers deliberately place ENIAC first in the list, so read the word commercially with care.

The correct answer is B, 1971. The Intel 4004 placed an entire processing unit on a single chip for the first time in a commercial product, and that step marks the beginning of the fourth generation of computers, built on very large scale integration. Everything that followed, including the personal computer, rests on it.

Option A, 1964, is the year of the IBM System 360, a landmark third-generation machine built on integrated circuits, which is why the year appears as a distractor. Option C, 1975, is associated with the early hobby computers of the microprocessor era but not with the 4004 itself. Option D, 1981, is the year the IBM Personal Computer was launched, a fourth-generation product rather than the first microprocessor. The safe way to remember the chain is 1947 transistor, 1958 integrated circuit, 1971 microprocessor.

The correct answer is C, RAM. Random access memory holds the programs and data the processor is working on at that moment, and it is volatile: the instant the power supply is cut, everything stored in it disappears. That is why unsaved work is lost in a power failure.

Option A, ROM, is read-only memory, written normally at manufacture and non-volatile, so it keeps the start-up instructions safely when the machine is switched off. Option B, the hard disk, is secondary storage and is non-volatile by design, since its whole purpose is to hold data permanently. Option D, EPROM, is erasable programmable read-only memory, a ROM variant whose contents can be wiped with ultraviolet light and rewritten, but it too retains data without power. The single word to test in such a question is volatile, and only RAM carries it.

The correct answer is B, 4 bits. A bit is the smallest unit of data, holding a single binary 0 or 1. Four bits together form a nibble, which is exactly half a byte, and a nibble is convenient because it maps neatly to one hexadecimal digit.

Option A, 2 bits, corresponds to no standard named unit. Option C, 8 bits, is a byte, the amount of memory needed to store one character, and it is the commonest distractor here because students remember the two units together. Option D, 16 bits, is often called a word on some machines, but word length varies with the processor and is not a fixed unit like the nibble. Above the byte the ladder rises in multiples of 1024: kilobyte, megabyte, gigabyte, terabyte, petabyte, exabyte, zettabyte and yottabyte. Learn the pair nibble four, byte eight together and read the question word carefully.

The correct answer is C, the Control Unit. It fetches each instruction from memory, decodes it, and then issues signals that tell the other parts of the system what to do and when. It manages the flow of data between memory, the arithmetic unit and the input and output devices, but it never performs arithmetic or a comparison itself.

Option A, the Arithmetic Logic Unit, is where all addition, subtraction, multiplication, division and logical comparisons actually happen, so it is precisely the unit the question excludes. Option B, cache memory, is a small very fast memory placed between the processor and main memory to hold frequently used data, and it is a memory rather than a control component. Option D, a register, is the smallest and fastest storage location inside the processor, used to hold an operand or an intermediate result for a moment. The CPU is the sum of the arithmetic unit, the control unit and the registers.

The correct answer is B, the third generation. The integrated circuit packs many transistors and other components onto a single silicon chip, and computers built on it were far smaller, cheaper and more reliable than their predecessors. The third generation also introduced the keyboard and monitor in place of punched cards and the operating system that allowed several programs to share the machine, with the IBM System 360 as the standard example.

Option A, the second generation, is the age of the individual transistor, not of chips carrying many of them. Option C, the fourth generation, is defined by the microprocessor and very large scale integration, where an entire processor sits on one chip. Option D, the fifth generation, is described in terms of ultra large scale integration, parallel processing and artificial intelligence rather than a single new component. The trap is that a microprocessor is itself an integrated circuit, so match the exact word the question uses.

The correct answer is D, the Centre for Development of Advanced Computing, usually written as C-DAC. PARAM 8000 was unveiled in 1991 under the leadership of Vijay Bhatkar, and it made India one of the small group of countries building their own supercomputers. It began the PARAM series, whose name comes from the Sanskrit word for supreme.

Option A, the Bhabha Atomic Research Centre, works on nuclear science and has its own computing facilities, but the PARAM line is not its project. Option B, the Indian Space Research Organisation, handles launch vehicles, satellites and space applications. Option C, the Defence Research and Development Organisation, develops defence systems and technologies. Each of these bodies appears in general knowledge papers for its own achievements, so keep the pairing firm: PARAM with C-DAC, and the year 1991 with Vijay Bhatkar as the scientist named in the question.

The correct answer is C, John von Neumann. He set out the idea that a computer should keep its instructions in the same memory as its data, so that a program could be loaded and changed like any other information instead of being wired into the machine. The design built on that idea is called the von Neumann architecture and is still the pattern of ordinary computers.

Option A, Charles Babbage, designed the Analytical Engine with a store and a mill and is the Father of the Computer, but his instructions came from punched cards rather than from memory. Option B, Ada Lovelace, wrote the first algorithm intended for a machine and is called the first programmer. Option D, Herman Hollerith, built the punched-card tabulating machine for the American census and founded the company that grew into IBM. The examinable phrase is stored program, and it belongs to von Neumann alone.

The correct answer is B, EPROM, erasable programmable read-only memory. A chip of this kind has a small quartz window, and shining ultraviolet light through it clears the stored contents so the chip can be programmed again. Until it is erased, it behaves like ordinary read-only memory and keeps its contents without power.

Option A, PROM, is programmable read-only memory, which is blank when made and can be written by the user exactly once; after that it cannot be changed at all. Option C, EEPROM, is electrically erasable programmable read-only memory, where the contents are wiped by an electrical signal rather than by light, which is why it can be updated while still inside the machine. Option D, DRAM, is dynamic random access memory, a volatile read-write memory that must be refreshed continually, so it is not a read-only memory at all. The key words are once, ultraviolet and electrically.