Objective c what kind of class are these page controls are from

Hey guys i like how these two applications have their page controls set up. how do you make these type of page controls? also what class are they from? please give me good details im new and just trying to understand thanks in advance.

http:开发者_如何学C//img26.imageshack.us/img26/1529/custompagemarkers.png

Those are what are called custom views. That is, people are creating them custom, they don't exist in the standard UIKit.