An array is a container object that holds a fixed number of values of a single type. The length of an array is established when the array is created. After creation, its length is fixed.

Array is the most important thing in any programming language. By definition, array is the static memory allocation. It allocates the memory for the same data type in sequence. It contains multiple values of same types. It also store the values in memory at the fixed size. Multiple types of arrays are used in any programming language such as: one - dimensional, two - dimensional or can say multi - dimensional.

Array, what is it? An array is a group of variables of the same data type and referred to by a common name. An array is contiguous block of memory locations referred by a common name.

You might come across a situation where you need to store similar type of values for a large number of data items.

For e.g.

To store the marks of 5000 students, you can declare an array, marks, of size 5000 and can store the marks of as many students.

int marks[] = new int[5000];

In computer science, an array type is a data type that is meant to describe a collection of elements (values or variables), each selected by one or more indices that can be computed at run time by the program. Such a collection is usually called an array variable, array value, or simply array.

At this point, you have dealt with only a few variables in each Java program. In some cases, it’s manageable to use individual variables to store information, but what if you had 20 items of related information to track? You could create 20 different variables and set up their initial values, but that approach becomes progressively more cumbersome as you deal with larger amounts of information. What if there were 100 items, or even 1,000?

Arrays are a way to store a list of items that have the same primitive data type, the same class, or a common parent class. Each item on the list goes into its own numbered slot so that you can easily access the information.

An array is a named collection of one or more items of data of the same type. Each element of data can be accessed by the name of the array and the numbered index indicating its position within the array.

In programming, a series of objects all of which are the same size and type. Each object in an array is called an array element. For example, you could have an array of integers or an array of characters or an array of anything that has a defined data type. The important characteristics of an array are:

•  Each element has the same data type (although they may have different values).

•  The entire array is stored contiguously in memory (that is, there are no gaps between elements).

Arrays can have more than one dimension. A one-dimensional array is called a vector ; a two-dimensional array is called a matrix.