An ordered arrangement of numbers or symbols is called an array.
For example, a VECTOR is a one-dimensional array: it is an ordered list of numbers.
Each number in the list is called a component of the vector.
A MATRIX is a two-dimensional array: it is a collection of numbers arranged in a finite grid. (The components of such an array are identified by their row and column positions.)
Two arrays are considered the same only if they have the same number of rows, the same number of columns, and all corresponding entries are equal.
One can also define three- and higher-dimensional arrays.
In computer science, an array is called an identifier, and the location of an entry is given by a subscript.
For example, for a two-dimensional array labeled A, the entry in the second row, third column is denoted A23.
An n-dimensional array makes use of n subscripts.
Text Source: Encyclopedia Of Mathematics Book