What is the use of namespace std?

Answer 1

To get direct access to variables and methods defined in the standard libraries that come in C++... cout and cin are a good example of this...if you don't declare "using namespace std" at the begining of your code then you will have to use std::cout and std::cin each time you want to use them.
You can also create you own namespaces when needed....
Hope it helped

Answer 2

getting standard library function

Answer 3

lib to use or remove is std::cout

Answer 4

thanks
can you please tell me how to create our own namespaces