Selected Computer Terms for True BASIC Book

algorithm: formal method for solving a problem using a

sequence of logical steps

application program: computer program that performs some

specific task; see editor

argument: value, variable, or expression attached to a procedure

name when the procedure is called

arithmetic operator: addition (+), subtraction (-), multiplication

(*), division (/), or exponentiation (^)

array: indexed variable that can store sets of numeric or string

values

ASCII: coding scheme used to represent characters in a digital

computer

assignment statement: LET keyword

assignment operator: the equal sign (=)

binary file: file of binary instructions

binary instruction: sequence of binary numbers that tells the

computer to do something

bit: binary digit, has value of 0 or 1

branch structure: program structure that chooses one of two or

more choices

bug: program error

built-in function: function that is part of the True BASIC

language

Bye command: exit the True BASIC system

byte: unit of eight bits

call: using a function name in an expression or using the CALL

statement

channel number: True BASIC identifying number for a file or

picture

Clear command: erase the current program, from File menu

click: press left mouse button when mouse cursor is on selected

object

command window: lower True BASIC window where

commands are entered

compiler: translates a source program into an object program

compound logical expression: two or more simple logical

expressions joined by one or more conjunctions

concatenation: join two strings together, operator is the

ampersand (&)

control variable: variable whose value determines when a loop

stops

CPU: central processing unit (an electronic chip) of a computer

current program: program presently running or in the editing

window

debugging: process of finding and removing program errors

decimal digit: digit appearing in a number after the decimal point

directory: named space on disk where files can be stored, DOS

term

disk: rotating magnetic platter where files are stored

display unit: televisionlike screen that displays text and graphics

double-click: click mouse twice in rapid succession

drag down: put cursor on menu title, hold mouse button down,

and pull down the menu

editing window: upper window where programs are edited

editor: computer program for creating and modifying files

element: single storage location in an array

EOF marker: character marking the end of a file

EOLN marker: set of two characters marking the end of a text

file line

equality operator: the equal sign (=)

error handler block: block of statements where each trapped

error is handled as directed by the program

external procedure: procedure placed after the program END

statement

file folder: named space on disk where files can be stored, a

MacOS term

file name: name associated with a specific file

file pointer: imaginary marker that marks some location in a file

file: named sequence of text characters or binary numbers,

usually stored on disk

final value: last value of a loop control variable

Find command: find a sequence of characters, from Edit menu

or command line

fixed disk: disk, usually non-removable, with high storage

capacity

floppy diskette: removable disk with low storage capacity

FUNCTION.TRU file: help file containing a list of all built-in

functions

function: block of computer statements that performs some

calculation and return a value

gigabyte: 1024 megabytes or about one billion bytes

global variable: variable that is used and known throughout a

program

GUI: graphical user interface that displays graphics on the

monitor screen

hard disk: see fixed disk

hardware: mechanical and electrical components of a computer

system

icon: little picture on a GUI that represents a program

indexed variable: see array

initial value: first value of a loop control variable

internal procedure: procedure placed before the program END

statement

keyboard: typerwriterlike device for entering characters into the

computer

kilobyte: 1024 bytes

line number: unique number identifying a program statement

local variable: variable that is first used and known within a

single procedure

logical expression: expression that has a value of only true or

false

logical function: function that returns a value of only true or false

loop structure: program structure that repeats a block of

statements several times

looping: process of executing a loop

machine language instruction: see binary instruction

MacOS: operating system for Apple Macintosh computers

megabyte: 1024 kilobytes or about one million bytes

memory address: location of a specific memory byte, expressed

in numbers

memory: electronic chips that store information in a computer

monitor: see display unit

mouse cursor: block or arrow cursor that moves when mouse is

moved

MS-DOS: Microsoft disk operating system for IBM PC-

compatible computers

multi-dimensional array: array with more than one index

nested loops: one loop enclosed entirely within another loop

New command: create a new program, from File menu

null string: an empty string, contains no characters

number: numeric value, a real number

numeric expression: formula or function that yields a numeric

value

numeric function: function that returns a numeric value

numeric variable: named memory location where a number can

be stored

object program: program of binary instructions

Old command: open an existing program, from command line

one-dimensional array: array with only one index

Open command: open an existing program, from File menu

operating system: software that supervises computer operations

and manages file directories or folders

output window: window where program results are displayed,

Version 5 or MacOS

parameter: variable attached to a procedure heading statement

pass: making values available to a procedure through arguments

and parameters

path name: file name plus directory name(s) specifying the

location of a file

PC-DOS: IBM disk operating system for IBM PC computers

printer: device to print computer output on paper

procedure: general term for a function or subroutine

program output: results produced when a program is executed or

run

program statement: language statement that when compiled, tells

computer to do something

programmed function: function written by a computer

programmer

protected block: block of statements where all errors are trapped

Quit command: exit the True BASIC system

RAM: random access memory, see memory

random number generator: mathematical expression that creates

random numbers

remark statement: non-executable program statement that makes

a comment

returns: makes the value stored in a function name available to

the calling unit

root directory: primary disk directory from which all others

branch

Run command: execute the current program, from Run menu or

command line

Save As command: save the current program with a new name,

from File menu

Save command: save the current program, from File menu or

command line

seed value: initial value used to start a random number generator

sentinel: variable that indicates whether some action has or has

not taken place

single-step: execute a program statement by statement by

pressing a key for each step

software: operating system and application programs of a

computer system

source program: program of language (True BASIC) statements

source window: window where the source program is

displayed, Version 5

STATMENT.TRU file: help file containing a list of all program

statements

string expression: formula or function that yields a string value

string function: function that returns a string value

string variable: named memory location where a string can be

stored

string: string value, a sequence of one or more ASCII characters

subroutine: block of computer statements that performs some

task

substring: designated part of a string

TERMS.TRU file: help file for computer terms and their

definitions

text cursor: underline or I-beam cursor showing insertion point

of the next character

text file: file of ASCII text characters

trapping: process of finding a program error and allowing the

program to handle it

True BASIC: advanced BASIC language, complies with the

ANSI BASIC standard

two-dimensional array: array with two indices

user-friendly: property of a program that makes it easy to use

variable value: numeric, string, or array value stored in a named

memory location

variable: named memory location where information can be

stored

Windows: Microsoft GUI usually combined with MS-DOS