Aqa A Level Computer Science Key Terms With All Passing Tips.

AQA A LEVEL COMPUTER SCIENCE KEY v v v v v




TERMS WITH ALL PASSING TIPS
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Absolute Error - correct answer-The difference between the actual number and the
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nearest representable value.
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Abstract data type (ADT) - correct answer-A data type whose properties are
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specified independently of any particular programming language.
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Abstraction - correct answer-Representation that is arrived at by removing
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unnecessary details.
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Aggregation - correct answer-Relationship between two object types in which one
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object type has a component which is of the other type.
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Ajax - correct answer-Web technology that allows only the part of a web page that
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needs updating to be fetched from the web server.
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Algorithm - correct answer-A sequence of unambiguous instructions for solving a
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problem. It can be represented as a Turing machine program.
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Application programming interface (API) - correct answer-A layer of software that
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allows application programs to call on the services of the operating system.
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Association - correct answer-If the relationship is not inheritance and it is not
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aggregation then it is an association.
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Asymptotic behaviour of f - correct answer-It is the behaviour of the function f(n) for
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very large values of n.
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, Asynchronous serial data transmission - correct answer-Transmission system in vb vb vb vb vb vb vb vb vb




which the sender and receiver have separate clocks which are not kept
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synchronised. Instead, the clocks are synchronised temporarily at the start of a
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transmission. The arrival of data cannot be predicted by the receiver; s a start bit is
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used to signal the arrival of data and to synchronise the transmitter and receiver
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temporarily.
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Attribute - correct answer-A property or characteristic of an entity (databases) or an
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object (OOP).
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Automation - correct answer-Turning an abstraction into a form that can be
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processed by a computer.
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Backus-Naur Form, (BNF) - correct answer-Backus-Naur Form, (BNF) vb vb vb vb vb vb vb vb




Bandwidth - correct answer-For a transmission medium, the range of signal
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frequencies it may transmit.
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Base case - correct answer-A value that has a solution which does not involve any
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reference to the general case solution.
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Baseband system - correct answer-A system that uses a single data channel system
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in which the whole bandwidth of the transmission medium is dedicated to one data
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channel at a time.
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Basic operation - correct answer-The operation which contributes most to the total
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running time.
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Baud rate - correct answer-The rate at which signals on a wire may change.
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Behaviours - correct answer-The functions of the object or what the object does.
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Bit rate - correct answer-The number of bits transmitted per second
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Broadband - correct answer-A multiple data channel system in which the bandwidth
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of the transmission medium carries several data streams at the same time.
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Bubble sort - correct answer-A sorting algorithm where during a pass, neighbouring
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values are compared and swapped. Passes are made until no further swaps are
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needed.
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Cipher text - correct answer-Message data after it has been encrypted.
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Circular queue - correct answer-When the array element with the largest possible
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index has been used, the next element to join the queue reuses the vacated location
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at the beginning of the array.
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Class definition - correct answer-A template that can be used to create objects of
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that class.
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