[AS2] How do I Create Object-Orientated Functions?

[Vadersapien]

Hello to all,
I would like to know how to create an object-orientated functions in Actionscript 2. I'm actually not sure if that is what it's called...please correct me if I'm wrong. Anyway here's an example of how I want to be able to call my functions:

missile.create(); 

or

missile.fire();