Variable types

Data types are used in programming to assign specific semantics to memory areas. These memory areas are called variables or constants. A differentiation is made between elementary, composed and abstract data types.

Elementary (simple) data types can contain only one date of the corresponding value range. They have a defined number of values (discrete) and a fixed upper and lower limit (finiteness). A distinction is made between ordinal and non-ordinal data types.

Ordinal data types are characterized by an unambiguous ordinal number that is assigned to their value. That means that every value, except for the first one, has a direct predecessor and every value, except for the last one, has a direct successor (ordered set). Ordinal data types are countable and include: INTEGER, WORD, BOOLEAN, CHAR.