Algorithm- a finite string of clearly defined operations necessary to perform a certain type of tasks, way of proceeding leading to solution of a given problem.

Compiler - a program used for automatic translation of the given code written in one language (source language) into the equivalent code in another language (most often machine language).

Constructor - a method of class called while creating its instance (creating the object).

Destructor - a method called while destroying the instance of class.

Encapsulation - hiding certain elements of classes not to be visible outside.

Inheritance - a mechanism of sharing functionalities between classes.

Instance - a concrete object of a given type (class) created.

Machine code - a set of processor’s orders, in which the program is expressed in the form of binary numbers constituting orders and their arguments.

Object-oriented programming - a programming paradigm in which programs are defined by means of objects - elements linking the state (i.e. data) and behaviour (i.e. methods).

Overloading - creation of several functions with the same names but with different parameters.

Pointer - a variable storing the memory address to a given object.

Polymorphism - mechanisms allowing a programmer to use values, variables and subprograms in several different ways.

Programming language - a set of rules which describe how to correctly build expressions comprehensible to the compiler.

Recursion - a function calling itself.

Subprogram - a separated part of program performing some operations, possible to be performed while realizing the program.

Source code - a computer program entry by means of a specific programming language.

Variable - a programming structure having three basic attributes: symbolic name, place of storage and value.