Well i'm a little confused, on this forum it says PHP stands for Hypertext Preprocessor, But on this course and in books it says it stands for Personal Homepage.

Which one is right?

When it was created i believe it was personal homepage, but as more people started usiing it and it became more developed it was changed to a recursive acronym "PHP: Hypertext Preprocessor"

But it still see the PHP in

"PHP: Hypertext Preprocessor"

It's a computer geek's idea of a joke - you never find out what the P stands for since it is recursive. Other examples of recursive acronyms include:
GNU = Gnu's Not Unix
WINE = Wine Is Not an Emulator
and
The TTP Project (this one is from a Dilbert cartoon)

Oh, so those dude at PHP are laughing there heads off that noone will know what the P stands for?

go dilbert!

The full descriptive name for PHP is Hypertext Pre-Processor, and the acronym probably came from a switching around of the Pre at some point to Pre Hypertext Processor, which really describes what it is.

May have been to avoid trade name conflicts with Hewlett Packard