Please explain the following function

This is a feature provided by the C++ called operator overloading . Using this you can change the meaning of operator if it is used in context of your class object.

Have a look at the following code.

Class YourClass
{

public :

int operator*(vector &y)
{
body

}

};

main ()
{
   vector v;
   YourClass y;
   y*v;    ///Here operator* function will be called and v will be passed as a parameter

}