Ph.D. and B.S. words origin

[Clausius2]

Your educational system involves the Ph.D and B.S titles. But I have never known which is the historical origins of this words (Doctor of Philosophy, Bachelor of..etc). They look like stated by the former british imperium.

Anyone knows about it?

Thanks in advance.

[cronxeh]

http://en.wikipedia.org/wiki/Bachelor%27s_degree

http://en.wikipedia.org/wiki/Doctorate