include and using namespace in C++

Question

for using cout, I need to specify both:

#include

and

using namespace std;

Answer 1

The #include references the header file that defines cout. If you're going to use cout, then you will always need the include.

You do not need to using namespace std;. That's simply allows you to use the shorthand cout and endl and the like, rather than std::cout and std::endl where the namespace is explicit. Personally I prefer not to use using namespace ... since it requires me to be explicit in my meaning, though it is admittedly more verbose.