[Solved] What does the namespace std add? (C++) [closed]

Question

1 – All the entities (variables, types, constants, and functions) of the standard C++ library are declared within the std namespace. using namespace std; introduces direct visibility of all the names of the std namespace into the code.

ref: http://www.cplusplus.com/doc/tutorial/namespaces/

2 – Namespaces in C++ are most often used to avoid naming collisions. Although namespaces are used extensively in recent C++ code, most older code does not use this facility. For example, the entire C++ standard library is defined within namespace std, but before standardization many components were originally in the global namespace.

ref: http://en.wikipedia.org/wiki/Namespace#Use_in_common_languages

Accepted Answer

1 – All the entities (variables, types, constants, and functions) of the standard C++ library are declared within the std namespace. using namespace std; introduces direct visibility of all the names of the std namespace into the code.

ref: http://www.cplusplus.com/doc/tutorial/namespaces/

2 – Namespaces in C++ are most often used to avoid naming collisions. Although namespaces are used extensively in recent C++ code, most older code does not use this facility. For example, the entire C++ standard library is defined within namespace std, but before standardization many components were originally in the global namespace.

ref: http://en.wikipedia.org/wiki/Namespace#Use_in_common_languages