Keyword (computer programming)

The term keyword (english keyword) or reserved word in a programming language called a word (English token ) that has a particular meaning by the definition of this programming language, and should not be used as the name of functions or variables. All reserved words are known to the compiler and the programming language used in the lexical analysis.

Keywords are the "vocabulary" of any programming language; therefore, one tries to minimize the number for the purposes of learnability. One can in appropriate programming textbooks or the Internet for almost any language an overview, find a so-called reference table.

It should be noted that the virtually endless variety of programs and applications through such a relatively minimal vocabulary (rarely more than 50 keywords ) can be realized.

Furthermore keywords in most programming languages ​​can be grouped into categories. For example, in object-oriented programming language Java, the access modifiers (such as public, protected, private ) or the primitive data types (eg, boolean, char, int) differed in such categories.

Comparing their references with programming languages ​​such as C and its extension C or other high level languages ​​it is found that there are a number of matches.

Keywords are frequently used are:

• Int, char, float - Primitive Data Types
• For, if, while, - control structures.

Straight extensions of programming languages ​​naturally fall back on the language scope of its predecessor and expand it if necessary. Another reason for a variety of use repeatedly keywords can be found in the history of programming languages.