Array

An array is a data structure that stores data/ elements directly next to each other. 
Every single Date/ element that is stored in the array have an index.
Indices start from 0 till the length of array-1. Index ∈ [0,  length of array-1].
Arrays have fixed size/ length and they are mutable. 

Types of Arrays :

• Linear array/ one-dimensional array.
• Two-dimensional array.
• Multi-dimensional array.

The simplest type of data structure is a linear/ one-dimensional array.

Linear array consists of elements that are stored next to each other in a linear way.

Two dimensional array consists of elements that are stored in many linear arrays under each other.
More precisely, there are rows and columns.

Multi-dimensional array is just a number of two dimensional arrays next to each other.