What is the past perfect tense of the spanish verb haber?

I know its hube. When is it used?

Why is this site (http://www.studyspanish.com/lessons/pastperfect.htm) telling that "In Spanish, the past perfect tense is formed by using the imperfect tense of the auxiliary verb "haber" with the past participle."

Thank you for your serious replies.

?2014-11-28T13:28:54Z

Si yo hubiese tenido dinero, hubiera comprado un carro. Pero al haber comprado el carro también necesitaría seguro.

Pero Carlos ha de haber agarrado lo mismo que yo, el también necesitaría seguro.

That's an example on I use that word when talking to anyone. Also, there's a big difference between Spanish from the America continent and from Spain. So, the Spanish from that website could be from Spain and just not an accurate Spanish.

Thanks for sharing and if you have any more questions, I'll be happy to assist.