# Linear data structure:

A data structure is said to be linear if its data item form a linear sequence.

Examples of the linear data structure are:

(a) Array (b) Linked List (c) Stack (d) Queue

## Array:

An array is a collection of data elements of same datatype.

The elements of the array are stored in consecutive memory locations.

Arrays are declared using the following syntax: type name[size];

memory representation:

## Stack:

A stack is a linear list in which insertion and deletion operations are performed at only one end of the list.

- It follows LIFO structure.

## Queue:

A queue is a linear list in which insertion is performed at one end, called rear and deletion is performed at another end of the list, called front.

- It follows FIFO structure

## Linked List:

A linked list is a collection of nodes. Each node has two fields: (i) Information (ii) address, which contains the address of the next node.

# Non Linear data structure:

A data structure is said to be non linear if its data items does not form a linear sequence.

Examples of the non linear data structure are:

(a) Tree (b) Graph

## Tree:

Tree is a collection of nodes (V) and edges (E) that follows hierarchical relationship.