A (one-dimensional) *array* (also
called a *vector*) is a set of
variables of a certain type `T`

that are all indexed by
an interval of integer numbers. The individual
variables of an array can be accessed via the indices.

Whereas arrays always start with the index 0 in C and C++ and their size cannot be changed at runtime without further effort, LEDA arrays can have any arbitrary interval as index set and their size can be adjusted at runtime to the actual space requirements.

In addition, LEDA provides two-dimensional arrays, whose index set is an arbitrary rectangle of integral coordinates of the plane.