Poor Man's Computer Dictionary

A

Argument

A value passed to a function, matching one of the function's parameters

Array

A variable type that stores an ordered collection of values of the same sub-type (known as elements)

Assignment

The process of giving a variable a value

B

Boolean

A variable type that is only either true or false

Bug

A mistake in the code that causes wrong or unexpected results

C

Char

A variable type that contains a single character, such as a letter, numeral or symbol

Code

A set of instructions to be interpreted by a compiler; typically stored in one or more files

Compilation

The process by which a set of instructions (code) is compiled into an executable program

Compile-time

Refers to any action that takes place while a program is being compiled, as opposed to when the program is running

Compiler

The tool used to compile a program

Computer Language

A structured and standardized method of writing code which is guaranteed to be understood by the associated compiler and/or interpreter

Concatenate

To combine two or more Strings together into one String

Console

A tool for running programs and interacting with them using text-based I/O
Command Prompt is the standard console in the Windows OS

CPS

Computer Science, the study of the principles and use of computers. Often used loosely to refer specifically to computer programming

D

Data

Information, in a form that can be used by a computer

Directory

Also known as a folder; a location on a computer which stores files

Double

A variable type that can store both whole numbers and decimals

E

Escape Sequence

A sequence of characters used to obtain a special character; consists of a backslash ('\') followed by a single character
Example: the escape sequence for the Newline character is \n

Exception

An error while running a program, normally resulting in the program crashing

Execution

The technical term for running a program

F

File

A container for data, information, settings, or commands on a computer; mostly divided between files that store text (like non-commpiled code) and files that store commands for the computer (like executable files)

Filename Extension

The letters after the dot (.) at the end of a file's name, specifying the type of file; typically hidden from normal users

Function

A container for code, which can be run (called) multiple times and from different places in a program
When a function is called, it can be passed arguments that match each of its parameters
When a function finishes running, it returns a value to the code that called it

G

GUI

The Graphical User Interface, or what the user sees; consisting of parts such as windows, buttons and images, among other things

H

I

Integer

A variable type storing positive and negative whole numbers

I/O

Stands for Input/Output; refers to how the user communicates to the computer and how the computer communicates to the user

J

K

Keyword

A word that has particular significance to the compiler and therefore cannot be used as a variable or function name
Example: static

L

Literal

A literal value, as opposed to a variable containing a value

M

N

Newline

A special, invisible character that causes text display to go to the next line; corresponds to the Enter key on a keyboard

O

OS

Stands for "operating system"; refers to the computer's "master" program that coordinates all the other programs the user is running
The OS is also responsible for helping programs communicate with the hardware: physical devices like the screen, keyboard and mouse
Windows, Linux and Mac OS are examples of different OS's

P

Parameter

Defines the type for an argument being passed to a function

Program

General term for an executable set of instructions stored in a single file

Q

R

Run-time

Refers to any action that takes place while a program is running, as opposed to when the program is being compiled

S

Scope

The 'space' within which a variable or function exists

Statement

A conceptually single instruction in code; in many languages ends with a semicolon (;)

String

A variable type containing a string of characters

Syntax

The (sometimes nit-picky) rules by which a computer language is written.
Example: In many languages (including Java), you must put a semicolon (;) at the end of every statement

T

Type

The type of a variable determines what kind of information can be stored in it.

U

V

Variable

A container for information whose contents can be changed (or varied) while the program is running. Every variable should have a defined type.

W

X

Y

Z