AQA A LEVEL COMPUTER SCIENCE - TOPIC 4 THEORY OF COMPUTATION

AQA A LEVEL COMPUTER SCIENCE -
TOPIC 4 THEORY OF COMPUTATION




what is an algorithm? - correct answer--An algorithm is a sequence of steps that can
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be followed to complete a task.
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-An algorithm always terminates rather than going on forever in a loop.
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describe abstraction in a representational way and general way? - correct answer--
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representational abstraction is removing unecessary details from a problem
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- A grouping by common characteristics to arrive at a hierarchical relationship of the
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b"is a kind of" type.
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describe information hiding and procedural abstraction - correct answer--
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Information hiding is defined as the process of hiding all details of an object that do
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not contribute to its essential characteristics. For example, if you're designing a
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program that works out how many cars can fit onto a ferry, information about the
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manufacturer or the colour of a car can be disregarded and just information about
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the size and weight of cars retained.
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