## Data structures:

A** data structure** is a way of organizing data items such that data items can be

accessed efficiently.

Or

A** data structure** is a way of organizing data items that considers not only the

items stored, but also their relationship to each other.

## Types of data Structure:

**Primitive data structure:**

The data structures that are directly operated by machine level instructions are

known as primitive data structures.

Following are the primitive data structure:

**(a) Integer :**

– Integer is a represent numbers.

– The set of integer is:

{…………-(n+1), -n,…,-2,-1,0,1,2,……..,n,n+1,………}

**(b) Real:**

– The number having decimal point is called real number.

– In this method the real number is expressed as a combination of mantissa and exponent.

**(c) Character:**

– Any symbol from the set [a-z][A-Z][0-9] and from other special symbol.

– A character is represented in memory as a sequence bits.

**(d) Logical:**

– A logical data item is a primitive data structure that can assume the value of either “true” or “false”.

– Most commonly used logical operators are AND, OR, and NOT.

**(e) Pointer:**

– Pointer is a variable which stores the memory address of other variable.

– It provides faster insertion and deletion of elements.

**Non Primitive data structure:**

The data structures that are not directly operated by machine level instructions are known as non-primitive data structure.

There are two types of non primitive data structure:

**1. Linear Data Structure**

**2. Non Linear Data Structure**