I recently read a blog entry that was talking about why some programmers have problems using an API that makes use of the factory pattern. The entry tries to break programmers down into categories based on how they go about the task of programming, how they investigate APIs, and how tight or broad their focus lies.
This got me thinking. How do most programmers discover a new API? What is the first thing you do when you realize you need to use the ABC class (or group of classes in a namespace)? Do you open your copy of MSDN? Do you go straight to Google (or your favorite search engine)? Do you create a test application and just poke around with the classes, use the IDE's intellisense to investigate all the operations it can offer? Do you open Reflector and read its code? Do you just ask the guy next to you?
What techniques do you use to explore and learn an unknown API?