Data Types
Data types in C refers to an extensive system used for declaring variables or functions of different types. The type of variable determines how much space it occupies in storage and how the bit pattern stored is interpreted.

The data types can be classified as:

• Basic Types: They are arithmetic types and are further classified into (a) integer types and (b) floating-point types (c) void types.
• Derived Types: They include (a) Pointer types, (b) Array types, (c) Function types.
• User-defined Types: They are (a) Enumeration types (b) Structure types (c) Union types.

1. Basic Types: The fundamental data types are called basic data types.

To get the exact size of a type or a variable on a particular platform, you can use the sizeof operator. The expressions sizeof(type) yields the storage size of the object or type in bytes. Given below is an example to get the size of int type on any machine.

#include <stdio.h>
#include <limits.h>
int main()
{
 printf("Storage size for int : %d \n", sizeof(int));
 return 0;
}

The header file float.h defines macros that allow you to use these values and other details about the binary representation of real numbers in your programs. The following example prints the storage space taken by a float type and its range values:

#include <stdio.h>
#include <float.h>
int main()
{
 printf("Storage size for float : %d \n", sizeof(float));
 printf("Minimum float positive value: %E\n", FLT_MIN );
 printf("Maximum float positive value: %E\n", FLT_MAX );
 printf("Precision value: %d\n", FLT_DIG );
 return 0;
}

Storage size for float : 4
Minimum float positive value: 1.175494E-38
Maximum float positive value: 3.402823E+38
Precision value: 6

1. Pointer types
2. Array types
3. Function types

You will learn about these derived data types in a later chapter.

1. Enumeration types
2. Structure types
3. Union types.