Abstract class

A class that cannot be instantiated

Abstract method

A method with a name,parameter types, and return type but without an implementation.

Algorithm

A list of simple steps, unambiguous to solve a problem. The steps have to be executable and the algorithm has to have an end.

Applet

A graphical Java program that executes inside a browser or an applet viewer.

Binary file

A file in which values are stored in their binary representation and cannot be read as text.

Command Line

The line you type when you start a program in a command window in DOS/WINDOWS or UNIX. It consist of the program name and the command line arguments.

CPU (Central Processing Unit)

The part of the computer that executes the machine instructions.

Constant

A value that cannot be changed by a program. In Java, constants are defined with the keyword final.

Variable

The name of a value that can be changed by a program. In Java, variables are defined using identificators.