What is Declaration ?

• To Declare is nothing but to represent a variable.
• Only Variable name and its Data type is Represented in Declaration.

Facts about Declaration :

1. Memory is neither allocated to Variable nor space is Reserved after declaration.
2. Declaration is just used for Identification of Data Type.
3. Re-Declaration of variable will cause compile Error.

int ivar;
int ivar = 10;

It will cause compile error. We cannot re-declare variable.

4. We cannot use variable inside program expression or in program statements without declaring.
5. Declaring a variable just give rough idea to compiler that there is something which is of type “<Data Type Specified>” and will be used in the program.

Example Of Declaration :

int ivar;

float fvar;

char cvar;