it's a inbuilt function but it don't return any value 
because void is used to return a charachter value.

it's actually user defined built in function...... since we
the user gave the function name as main() when we write the
coding for the compailer........

main () is user defined function built in function.....
bcoz we define what it will do... and it already has it's 
name as main.

Its a user defined function. How can it be inbuilt 
function? We are the one who writes the main function. 
Program execution starts with main function. We can also 
compile a code without main, but we cant create exe, since 
it requires a main function to execute.

main() itself is a predefined function.

where as main() is a userdefined function because there we 
are writing the internal part.

main() is a user defined function. it is the entry point of 
any program. 
At run time the main() function is searched as the entry to 
start the program.

main is a system declared user defined function

it is an inbuilt function i.e, main() it indicates the
starting of the program and it is a user defined function
when the user defines it as void main() or int main(void).

it is built in function because (main )codings are written 
by the software developer.so,we cant change anything in 
this built in function.but user defined functions are 
changed by us.
so it is built in function