What is the difference between local and global variable of C language?

4m Sai. Gloabal Variable is variable which is declared before main (). int a=10; main() { } here a is a global variable. where ever u r using this variable ... we'll get the value as 10. Local Variable is a variable which is declared inside the main(). int a=10; main() { int a=5; ........ ....... } here a=5 is a local variable and a=10 is called as global variable. then if u want to get a value... printf("%d",a); then result 'll be a=5; B'cos compiler gives main preference to local variables.. if any local declareation is not there then it 'll prefer global variable.