I am new in Unix. I go through the man strip. But did not understand that, why when we have -G (debug and release ) option in the compiler, than using strip command to strip the debug information from the objects. i want to binary for teh production i will compile it without debug option. What the exact scenario where strip command is useful.
Thanks in advanced.

using strip to remove debugging information from a production binary or creating a production binary without symbol table information / debugging information is highly not recommended

what if the binary crashes in the production ?

With the debugging information / symbol table information, it would be very helpful for debugging.

Ok. Like i have created one binary with the debug option debug.out and another without it is production.out. Now, i will stripe the debug.out. Now, both binary will be same? or have any differences.

no they won't be the same

the answer is in your question ..
stripped version - will not have debugging symbols, symbol table

unstripped version - will have all the necessary information to debug on a core or to debug a running process

stripped version - would be helpful ( not always and it is subjective ) when binary needs to be transferred to another host for execution, run test for batch builds something of that kind

thanks Mtarix