Fundamentals Questions and Answers

Answer: A

Correct answer: Binary Coded Decimal

BCD encodes each decimal digit separately in four bits, so 59 is stored as 0101 1001 rather than as the binary 111011. It wastes space, since six of the sixteen combinations are unused, but it converts to and from decimal without rounding - which is why it survives in financial and display applications.

Answer: C

Correct answer: Plotter

A plotter draws continuous lines rather than approximating them from dots, so curves and diagonals come out smooth at any size. For large technical drawings that is a quality no raster printer of the period could match.

Answer: B

Correct answer: Vacuum Tubes and Valves

First-generation computers (about 1940-56) - ENIAC, UNIVAC - switched with vacuum tubes. They were enormous, consumed great quantities of power, generated much heat, and failed often, since a machine with 18,000 tubes will always have one about to burn out. The transistor, in the second generation, cured all four problems at once.

Answer: B

Correct answer: Plotter

A plotter draws with pens or heads that move continuously over the paper, so it produces smooth, precise lines at large size - which is what engineering and architectural drawings need. A monitor gives no hard copy at all; the printers give raster output, which is fine for text but coarser for large line drawings.

Answer: C

Correct answer: Both of above

An instruction has two parts: the opcode, which says what operation to perform, and the operand, which says what to perform it on - a value, a register, or a memory address. Some instructions have several operands and a few have none, but the opcode is always present.

Answer: A

Correct answer: ENIAC

ENIAC (1946) was regarded as the first general-purpose electronic computer until 1973, when a United States court, in Honeywell v. Sperry Rand, invalidated its patent on the ground that its ideas had been derived from Atanasoff’s earlier work - and named the ABC as the first electronic digital computer.

Answer: C

Correct answer: USA

The digital computer was developed chiefly in the United States - Atanasoff at Iowa State, Aiken at Harvard, and Eckert and Mauchly at Pennsylvania, who built ENIAC and then UNIVAC. Britain contributed Colossus and the Manchester machines, and Zuse worked in Germany, but the main line of development, and the first commercial machines, were American.

Answer: B

Correct answer: Buffer

A buffer is a holding area between two units that work at different speeds - the processor and a printer, say. The fast device deposits data and carries on, and the slow one takes it at its own pace, so neither has to wait for the other. An accumulator is a register in the ALU, and an address identifies a memory location.

Answer: B

Correct answer: 1906

Lee De Forest invented the triode vacuum tube, the Audion, in 1906, adding a control grid to Fleming’s two-element valve of 1904. The grid let a small signal control a large current - amplification, and with it electronic switching, which is what the first generation of computers was built from.

Answer: C

Correct answer: Lexical Analysis, syntax analysis, and code generation

A compiler works in phases: lexical analysis breaks the source into tokens, syntax analysis checks that they form valid constructions and builds a parse tree, and code generation produces the target code - with semantic analysis and optimisation in between. The other options describe the stages of a systems development project, not of compilation.