Computer Awareness Mixed Quiz: Set 23

The correct answer is B, Charles Babbage. Babbage designed the Difference Engine in 1822 and then the Analytical Engine, a general purpose mechanical computer with a store for numbers, a mill for arithmetic, punched card input and printed output, which is the plan of a modern computer drawn a century before one could be built; for that he is called the father of the computer. Option A is wrong because Blaise Pascal built the Pascaline of 1642, a mechanical adding machine but not a programmable computer. Option C is wrong because Alan Turing is called the father of computer science for the theoretical Turing machine of 1936. Option D is wrong because John von Neumann gave the stored program concept and the architecture named after him, a later contribution.

The correct answer is B, second. The generations of computers are named for the switching device they use, and the second generation, running from the late 1950s into the early 1960s, replaced the bulky vacuum tube with the transistor, which had been invented at Bell Laboratories in 1947. Transistor machines were smaller, cooler, cheaper and far more reliable, and IBM 1401 and IBM 7094 are the usual examples. Option D is wrong because the first generation used vacuum tubes or valves, as in ENIAC and UNIVAC-I. Option C is wrong because the third generation moved on to integrated circuits, many transistors on a single chip, as in the IBM 360. Option A is wrong because the fourth generation is defined by the microprocessor and very large scale integration, which began with the Intel 4004 in 1971.

The correct answer is B, Nibble. A byte is made up of eight bits, so half a byte is four bits, and four bits together are called a nibble. The term matters in hexadecimal arithmetic, because one hexadecimal digit represents exactly one nibble, which is why four binary digits convert neatly into a single hexadecimal character. A is wrong because a byte is the full group of eight bits, not half of itself, and it is the unit in which file sizes and memory are measured. C is wrong because a bit, short for binary digit, is the smallest unit of data and holds only a 0 or a 1, so it is one-eighth of a byte rather than one-half. D is wrong because word size is the number of bits a particular processor handles in one operation, which may be 8, 16, 32 or 64 bits depending on the machine, and is not a fixed fraction of a byte.

The correct answer is B, Datasheet. In a database such as Microsoft Access, the view that shows a table as rows and columns, looking like a spreadsheet grid, is called Datasheet view. Each row of that grid is one record and each column is one field, and the names along the top come from the field names set in Design view. Datasheet view lets you type data straight in, sort it, filter it and widen columns, while Design view is where the data type, field size and primary key are fixed. Queries and forms can also be opened in Datasheet view, so the name belongs to the display format, not to one object. Option A is wrong because a record is a single row of the grid, one complete entry, not the grid itself. Option C is wrong because a query is a saved question that pulls out selected rows; it is a database object. Option D is wrong because 'Tables' names the objects being displayed, while the question asks what the grid-like view is called. Exam tip: Access tables have two main views — Datasheet for data, Design for structure.

The correct answer is C, Blaise Pascal. The French mathematician Blaise Pascal built the Pascaline in 1642 to help his father with tax calculations; it worked with toothed wheels and could add and subtract, and the programming language Pascal is named in his honour. Option A is wrong because Gottfried Leibniz built the Stepped Reckoner in 1673, an improvement that could also multiply and divide, and he gave the binary number system. Option B is wrong because John Napier published logarithms in 1614 and devised the calculating rods called Napier’s bones. Option D is wrong because Joseph Marie Jacquard built a punched card loom in 1801; his cards influenced computing but his machine wove cloth rather than doing arithmetic. Pascal was only nineteen when he built the machine, and its wheels carried a tooth that passed the carry on to the next digit.

The correct answer is C, Graphics. In multimedia, graphics is the broad word for every kind of visual element a computer can store and show, so drawings, photographs, movies and simulations all sit inside it. The usual list of multimedia elements is text, graphics, audio, video and animation, and in that list graphics covers both pictures made by hand on the screen and pictures captured from the real world. Graphics are stored either as bitmaps, made of pixels, as in a JPEG or BMP photograph, or as vectors, made of lines and curves described by equations, as in a drawing or a CAD file. A is wrong because animation is only one kind of visual, a sequence of frames shown fast enough to look like movement. B is wrong because an image is a single still picture, so it is narrower than the four things listed. D is wrong because text is made of characters and carries no picture. Exam tip: multimedia elements are text, graphics, audio, video and animation; bitmap graphics use pixels, vector graphics use equations.

The correct answer is C, ROM. Read Only Memory is the permanent or non-volatile memory of a computer: its contents are written once and survive when the power is switched off, which is why the BIOS firmware that starts the machine and runs the power-on self-test is stored in it. A is wrong because RAM, or Random Access Memory, is volatile temporary memory; everything in it is lost the moment power is removed, which is why unsaved work disappears in a power cut. B is wrong because a CD-ROM is an optical secondary storage medium that you insert and remove, not the permanent internal memory built into the machine; the question asks for the computer's own memory. D is wrong because the CPU is the processing unit and not a memory at all, although the registers inside it do store a few values while a calculation is running.

The correct answer is B, Meta Search Engine. A meta search engine keeps no index of its own. It hands the user's query to several other search engines at the same time, collects what they send back, removes repeated hits and shows one merged list. Because it borrows from many sources, a single search covers more of the web than any one engine would on its own. Dogpile and Startpage work in this way. A is wrong because advanced search only means the extra filters an ordinary engine offers, such as date, file type or exact phrase, while it still searches its own index. C is wrong because search tool is a loose term for any utility that finds files or text, not a defined class of engine. D is wrong because Boolean searching refers to using AND, OR and NOT inside one engine, not to querying other engines. Exam tip: meta means about, so a meta search engine searches the searchers.

The correct answer is A, Ada Lovelace. Ada Lovelace, the daughter of Lord Byron, worked with Charles Babbage on the Analytical Engine, and the notes she published in 1843 include a step by step sequence for computing Bernoulli numbers on it, which is recognised as the first computer program; a programming language, Ada, is named after her. Option B is wrong because Grace Hopper came a century later and is remembered for the first compiler, for COBOL and for popularising the word debugging. Option C is wrong because Dennis Ritchie created the C language and co-created Unix in the 1970s. Option D is wrong because Konrad Zuse built the Z3 in 1941, a machine rather than a program. Lovelace also saw that such an engine might one day work on symbols and music and not on numbers alone.

The correct answer is D, the operating system will return an error indicating that the directory is not empty. The plain remove-directory command is built to delete an empty folder only. In Windows it is rmdir, also written rd, and in Linux it is rmdir; both stop with a message such as "The directory is not empty" when anything is still inside. To remove a folder along with everything in it you have to ask for it: rmdir /s in Windows or rm -r in Linux, which walks through the tree, deletes the contents and then the folder. This guard exists so that a single short command cannot wipe out a large tree by mistake. Option A is wrong because nothing inside is touched without the recursive switch. Option B is wrong because a file system cannot leave files with no parent folder; the entries go together or not at all. Option C is wrong because the plain command does not ask item by item, which is what an interactive option like rm -i does. Exam tip: rmdir empties only, rm -r for the whole tree.

The correct answer is A, Cache Memory. Cache is a small quantity of very fast static RAM placed between the processor and main memory to hold the instructions and data most likely to be needed next, and of the options given it has the shortest access time; only the registers inside the processor itself are faster. Cache is graded as L1, L2 and L3, with L1 nearest the core and quickest. D is wrong because random access memory is the main memory and is slower than cache, which is the whole reason cache exists. B is wrong because magnetic bubble memory is an old non-volatile technology that stored data as tiny magnetised regions in a thin film and was far slower than semiconductor memory. C is wrong because magnetic core memory, built from tiny ferrite rings, was the main memory of second generation computers and had access times measured in microseconds rather than nanoseconds.

The correct answer is C, Extended Binary Coded Decimal Interchange Code. EBCDIC is an 8-bit character encoding scheme developed by IBM in 1963 for its mainframe and midrange computers. Because it uses 8 bits for each character it can represent 256 different characters, twice as many as the 7-bit ASCII code, which handles 128. EBCDIC grew out of the older Binary Coded Decimal system and is still found on IBM mainframes, while ASCII became the standard for personal computers and Unicode now covers the scripts of the world, including Devanagari. A is wrong because the third word is Coded, not Control. B is wrong on two counts: the first word is Extended and the third is Coded. D is wrong because the expansion ends with Decimal Interchange Code, not Data Integration Code. Exam tip: EBCDIC is 8-bit and 256 characters, ASCII is 7-bit and 128 characters, Unicode is 16-bit and covers all scripts.

The correct answer is C, vacuum tubes. ENIAC, the Electronic Numerical Integrator and Computer, was completed in 1946 at the University of Pennsylvania by J. Presper Eckert and John Mauchly and used some eighteen thousand vacuum tubes; it was a first generation machine, filled a large room and consumed a great deal of power. Option A is wrong because the transistor was invented only in 1947, a year after ENIAC was finished, and defines the second generation. Option B is wrong because integrated circuits came in 1958 and define the third generation. Option D is wrong because the microprocessor arrived with the Intel 4004 in 1971 and defines the fourth generation. The heat and failure rate of tubes is why each later component mattered. ENIAC was also set up by throwing switches and plugging cables rather than by a stored program.

The correct answer is D, the input tag with its type attribute set to checkbox. HTML has no separate checkbox element at all. Every simple form control is written with the single input tag, and the type attribute decides what the browser draws, whether that is text, password, radio, checkbox, submit, file or hidden. So a checkbox is made by writing input and setting type to checkbox, while the name and value attributes tell the server which boxes were ticked. Several checkboxes may share one name, which lets a user pick more than one answer; radio buttons that share a name allow only one choice. Option A is wrong because checkbox is written there as a bare word instead of as the value of the type attribute. Option B is wrong because no checkbox element exists in HTML. Option C is wrong because the equals sign is placed straight after the tag name rather than inside a proper attribute. Exam tip: one input tag, many controls, and the type attribute is what changes.

The correct answer is B, Arithmetic Logic Unit. The ALU is the part of the processor that actually does the work on data: addition, subtraction, multiplication and division on the arithmetic side, and comparison along with the logical operations AND, OR and NOT on the logic side. Results produced by the ALU are placed in the accumulator register. A is wrong because the control unit performs no calculation; it decodes each instruction and issues the timing and control signals that direct the other units, which is why it is called the nervous system of the computer. C is wrong because the memory unit only stores instructions and data and hands them over when asked. D is wrong because the input unit merely accepts data from devices such as the keyboard, mouse and scanner and converts it into a form the machine can use.

The correct answer is C, C2B. In the consumer-to-business model the consumer names the price or the terms and the business then accepts or declines the offer, so the usual direction of an offer is reversed. Reverse-auction travel sites, where a traveller bids a price for a hotel room, and freelancers who quote their own rate to companies are everyday examples. The model spread with the internet, which let one individual reach many firms at once. A is wrong because B2B commerce is trade between two businesses, such as a parts maker supplying a car factory. B is wrong because B2C commerce is a business selling directly to the end consumer, as a shopping website does. D is wrong because C2C commerce links one consumer with another through a platform, as online classified and resale sites do. Exam tip: read the pair in order - the first letter is who makes the offer, the second is who responds, so in C2B the consumer sets the price.

The correct answer is B, John Napier. The Scottish mathematician John Napier published his work on logarithms in 1614, which turned multiplication into addition, and he then devised a set of numbered rods, Napier’s bones, with which products could be read off mechanically. Option A is wrong because William Oughtred used logarithms to make the slide rule in 1622, a development of Napier’s idea rather than its origin. Option C is wrong because George Boole gave the algebra of logic in 1854, the basis of digital circuit design, not a calculating aid. Option D is wrong because Herman Hollerith built the punched card tabulating machine used in the United States census of 1890 and founded the company that became IBM. Logarithms turned long multiplication into simple addition and ruled scientific calculation until the pocket calculator arrived.

The correct answer is C, Program Counter. The program counter, sometimes called the instruction pointer, always holds the memory address of the next instruction the processor will fetch, and it is incremented automatically as each instruction is taken up so that execution moves forward in order; a jump or branch instruction works simply by loading a new value into it. A is wrong because the accumulator holds the operand and the result of the current arithmetic or logical operation, not an address. B is wrong because the instruction register holds the instruction that has already been fetched and is being decoded now, which is one step behind the program counter. D is wrong because the memory data register holds the data that has just been read from, or is about to be written to, a memory location, while its companion the memory address register holds that location's address.

The correct answer is C, 1971. Intel released the 4004 in 1971, putting a complete central processing unit on a single chip for the first time and beginning the fourth generation of computers along with the age of the personal computer. Option A is wrong because 1947 is the year the transistor was invented at Bell Laboratories by Bardeen, Brattain and Shockley, which opened the second generation. Option B is wrong because 1958 is the year of the integrated circuit, invented independently by Jack Kilby and Robert Noyce, which opened the third generation. Option D is wrong because 1981 is the year IBM launched its personal computer, an important fourth generation product but a decade after the microprocessor itself. The 4004 was a four bit processor built on an order from a Japanese calculator company.

The correct answer is B, John von Neumann. In 1945 John von Neumann described a design in which a computer's instructions and its data are both held in the same memory in the same binary form, so that the machine can be given a new task simply by loading a new program instead of being rewired. Almost every general purpose computer today follows this von Neumann architecture, whose opposite is the Harvard architecture with separate memories for instructions and data. A is wrong because Charles Babbage, the father of the computer, designed the Difference Engine and the Analytical Engine in the nineteenth century, long before stored programs in electronic memory. C is wrong because Alan Turing is remembered for the Turing machine, the Turing test and his codebreaking work, and is called the father of artificial intelligence. D is wrong because Blaise Pascal built the Pascaline, a mechanical adding machine, in 1642.