C++ ofstream vs basic_ofstream

I am confusion.

I'm learning about the ofstream, it seems that it's really a basic_ofstream according to:

• https://en.cppreference.com/w/cpp/io/basic_ofstream/basic_ofstream
• https://msdn.microsoft.com/en-us/library/7z434859.aspx

What is the reason for a class named basic_ofstream with a constructor named ofstream? 'basic' implies that there is a non-basic version. Why is the constructor name different than the class name?