25
SepData Types
The data type in C defines the amount of storage allocated to variables ,the values that they can accept ,and the operation that can be performed on those variables.
C is rich in data types. The verity of data type allow the programmer to select appropriate data type to satisfy the need of application as well as the needs of different machine.
There are three classes of Data-Type
Primary Data Type
Derived Data Type
User Defined Data Type
Primary Data Types(Fundamental Data Types)
All C compiler support five type of fundamental data type
Integer int 2,768 to 32,768
Character char -128 to 127
Floating Point float 3.4e-38 to 3.4e+38
Double Precision Floating Point double 1.7e-308 to 1.7e+308
Void Data Type void(used for function when no value is to be return)
Size and Range of Data-Types on a 16-bit machine
Note
Use sizeof() to know the size of int , char, float etc.
Example program to determine the max and min range of a particular data type.
#include<conio.h> #include<stdio.h> void main() { unsigned int i, j; i =1; o) { j = i; i ++; } printf("Maximum value of unsigned int is = %u", j); printf("Minimum value of unsigned int is = %u", i); }
Note
Do not use increment(++) or decrement(--) operator with floating points variable.
A simple program using different data types
#include<conio.h> #include<stdio.h> void main() { /*………Declaration part…………*/ char c; int x, y; float f1, f2; Double d1, d2; unsigned p; /*…………Assigning while declaring………*/ int a = 4321; long int l = 5432167; /*……………Assignment Part ………………*/ c = 'A'; x = 867; f1 = 4.3214; d1 = 8.5467342; f2 = 20.000; d2 = 3.0; /*………Displaying Values……………………*/ printf("c = %c \n", c); printf("x = %d and y = %d \n", x, y); printf("l = %ld \n", l); printf("d1 = %07lf \n", d1); printf("p = %u \n", p); }
User define Data type
By using a feature known as "type definition" that allows user to define an identifier that would represent a data type using an existing data type.
Note
General form: typedef  type  identifier;
or (to better understand)
typedef existing_data_type new_user_define_data_type;
Example Using user defined data type
typedef int number; typedef long big_ number; typedef float decimal; typedef double big_decimal; /********* now we can use above user defined types to declare variables********/ number visitors = 25; big_number population = 12500000; decimal radius = 3.5; big_decimal pie= 3.1415926535
Advantage
main advantage of typedef is that we can create meaningful data type names for increasing the readability of the program.
Derived Data Type
Those data types which are derived from fundamental data types are called derived data types.
There are basically three derived data types .
Array: A finit collection of data of same types or homogenous data type.
String: An array of character type.
Structure: A collection of related variables of the same or different data types.
note: Details of Array, String and Structure is available separately in this site.
Examples of derived data types.
/*...........Array...........*/ int roll_ no[40]; //Array to contain roll number of 40 students /*...........String...........*/ char name[20] = "Deepak Kumar"; //string of MAX 20 chars /*........... Structure...........*/ struct employee { char name[20]; int age; float salary; }; // Collection of different data types struct employee emp = {"Shakshi", 28, 450000.00};
What do you think?
By this article I have tried to explain different types of data used and their ranges in C language. I hope this article will be beneficial for you. Any comment and criticize will be welcome.
Take our free skill tests to evaluate your skill!

In less than 5 minutes, with our skill test, you can identify your knowledge gaps and strengths.