What is Static member function?

Static member functions are used to maintain a single copy of a class member function across various objects of the class. Static member functions can be called either by itself, independent of any object, by using class name and :: (scope resolution operator) or in connection with an object.

Restrictions on static member functions are:
1. They can directly refer to other static members of the class.
2. Static member functions do not have this pointer.
3. Static member function can not be virtual.

What are static member functions?

A static function can have an access to only other static members (functions or variables) declared in the same class.
A static member function can be called using the class name instead of its objects.
E.g. classname :: functionname;