Guide Questions Well Answered.
abstract data structure - Answer A way of organizing data and its related procedures and functions.
accessor methods - Answer Methods that do not alter the state or attributes of an object; their
purpose is to return information.
accumulator - Answer A storage register in the ALU that holds data temporarily while the data is
processed and before it is transferred to memory.
A-D converter - Answer Analog-digital converter. A device for converting analog signals into digital ones
for subsequent computer processing; sometimes called a "digitizer". A digital to analog (D to A)
converter operates in the reverse direction.
ADSL (Asymmetrical Digital Subscriber Line) - Answer Technology that increases the data rate over
existing telephone lines accommodating voice and digital data transfer. A special modem is needed for
access.
address bus - Answer Pathway from memory to processing unit that carries the address in memory to
and from which data is transferred. See the definitions for "bus" and "data bus".
algorithm - Answer An ordered set of well-defined instructions for the solution of a problem in a finite
number of steps.
ALU - Answer See the definition for "arithmetic and logic unit".
analog data - Answer The representation and measurement of the performance or behaviour of a
system by continuously variable physical entities such as currents, voltages and so on. See also the
definition for "digital data".
and - Answer The output of "and" is True if all statements are True, False if any statement is False.
,applet (Java) - Answer A program that runs in the context of a browser.
application (Java) - Answer A program that runs when translated by a Java compiler.
archive - Answer Data that represents a record of data held and processed at a specific time, which is
held off-line for future research or for legal reasons.
argument - Answer A value or object passed to a method when it is called.
arithmetic and logic unit (ALU) - Answer A part of the computer that performs arithmetic operations,
logic operations and related operations.
array - Answer 1. An arrangement of data in one or more dimensions.
2. In programming languages, an aggregate that consists of data objects, with identical attributes, each
of which may be uniquely referenced by indexing.
ASCII: American Standard Code for Information Interchange - Answer The primary encoding character
set used in computers for textual data transfer between applications. The set uses eight bits for each
character code, one of these bits being a check bit to verify the seven bits needed to represent one
character. ASCII supports most European alphabets. Unicode supports most known alphabets and is
increasingly used in data transfer. See also the definition for "Unicode".
attribute - Answer Element of data contained in an object; as specified within the object's class.
B - Answer Byte.
back-up (file) - Answer A second copy of a file, to be used in the event of the original file being
corrupted.
balanced tree - Answer A tree in which the right and left subtrees of any node have heights differing by
one at the most. See also the definition for "unbalanced tree".
, bar code - Answer A pattern of vertical lines distinguished from each other by width. It can be read by a
bar code reader to provide data to a computer.
bar code reader - Answer An optical reader that can read bar codes.
base - Answer The basis of a notation or number system, defining a number representational system by
positional representation. In a decimal system the base is 10, in a hexadecimal system the base is 16, and
in a binary system the base is 2.
batch processing - Answer A method of processing data in which transactions are collected and
prepared for input to the computer for processing as a single unit, for example, payroll.
behaviour - Answer The way in which an object reacts to the methods applied
BigO notation - Answer A notation used to describe the relative performance (speed) of an algorithm.
binary operator - Answer An operator that combines two operands to give a single result, for example,
addition, multiplication, division, mod, div. See also the definition for "unary operator".
binary search - Answer A search in which, at each step of the search, the set of data elements is divided
by two, until the searched element is found. See also the definition for "sequential search".
binary tree - Answer A tree in which each node has at most two children.
bit (b) - Answer Binary digit. The smallest unit of information for data storage and transmission. Each
bit is considered to be either a "0" or a "1".
block - Answer The smallest unit of data that can be transferred between memory and backing store in
one operation.
BMP - Answer An extension given to files in bitmap form.