Yes,
But the thing is here every data types and objects itself have a convertion function
toString which helps you to convert any type of objects to number or string. In .NET they have defined the separate class or module for the convertion. When calling the Convert object, what the compiler will do is it will load all the functions and properties of the Convert class and call your convertion function which will take a bit memory. Here we have just talked about how the flexible the program was. Really it is a good to understanding and do the coding. Anyway in each programming language, they are having the convertion functions. So we dont need to worry about it.
thanks