C Plus Plus using
From GMpedia.org Wiki
The using statement in C++ introduces the indicated namespace into the current declarative region.
Without 'using', you have to add the std:: namespace to the beginning of things like 'cout' & 'endl':
std::cout << "Hello!" << std::endl << name << "!" << std::endl;
With 'using':
cout << "Hello!" << endl << name << "!" << endl;
