### Array

Array are the simplest data structure. An array is a sequential list of elements

which is fixed in number. We can say an array is a fixed-sized, homogeneous

and widely used data structure.

**This definition of array consists of three important terms:**

By ‘homogeneous’, we mean that all the elements of an array are of the same

type known as element type or base type.

By fixed sized we mean that the number of elements in array are constant and

so does not change during the lifetime of the structure.

Array is the simplest data structure so it is widely used.

An array is also called a random-access data structure. Because all elements

can be selected at random and are equally accessible. An array can be used to

structure several data objects in the programming languages. Any element of an

array is selected by giving its subscript, which is an integer indicating the position

of the component in the sequence.

Therefore, we can say that an array is made of the pairs (value, index) which

mean that with every index, a value is associated. An index value is a number

used to identify an array element. If every index is one single value then it is

called a one-dimensional array, whereas if every index is a n-tuple

{ i1, i2, i………in}, the array is called a n-dimensional

array.

When dealing with arrays, each cell has its own index number. Typically, the

very first cell has an index of 0, but that doesn’t always have to be the case,

as you shall see latter on.