glossary

Glossary

Absolute Error - difference between true resultant value and nearest representable value

ADC (Analogue-to-digital converter) - to sample electrical equivalent of sound and convert sample into digital signal using two voltage levels

Algorithm - a process or set of rules to be followed in calculations or other problem-solving operations, especially by a computer.

Analogue Data - data that varies in a continuous manner

Assignment - storing data into a variable, giving that data a memory location

Bitmap - defines a display space and the colour for each pixel or "bit" in the display space

Bits - the smallest unit of data in a computer, has a single binary value: 0 or 1

Bytes - 2nd smallest unit of data, 8 bits or 2 nibbles

Compression - process of reducing the number of bits required to represent data

DAC (Digital-to-analogue converter) - to playback recorded sound

Even Parity - a parity checking mode in which an extra bit, called a parity bit, is set to 1 if there is an even number of 'one' bits in a one-byte data item.

Hz (Hertz) - unit of frequency (used to measure wave frequencies, such as sound waves)

Iteration - also known as looping; process where a set of instructions are repeated until a condition is met

Nyquists Theorem - "sound must be sampled twice its highest analogue frequency in order to extract all of the information from the bandwidth and accurately represent original acoustic energy"

Odd Parity - a parity checking mode in which an extra bit, called a parity bit, is set to 1 if there is an odd number of 'one' bits in a one-byte data item.

Overflow - where the value is too large to be represented using the available number of bits

Pixel - the smallest representable element of an image that can be individually processed

Precision - maximum number of significant digits that can be represented

Pseudocode - a notation resembling a simplified programming language, used in program design

PCM (Pulse-code modulation) - a method used to digitally represent sampled analog signals

Relative Error - absolute error divided by the true resultant value

Resolution - the number of pixels within an image, expressed in terms of horizontal x vertical axis

Selection - also called decision; program takes course of action depending on the answer e.g. if statement.

Sequence - where an action or event leads to the next ordered action in a predetermined order

Underflow - where the value is too small to be represented using the available number of bits

Vector - co-ordinate based image that does not have a reduction in clarity when zoom is increased or decreased

Bubble Sort- a simple algorithm  that compares based off each pair.