What is the difference between Builder Pattern with static inner class and Builder design patterns with One Abstract and one+ concrete implimentations

I am learning about builder design pattern, I found two explanations of the same.

1. With a static inner builder class which returns object of outer class appropriately.
2. With One Builder Abstract class, then more than one implementations of the same and one director class.

I am totally confuse over which one it is? or is it both?