What is the effect of a hard reset ?

[sonofliberty]

Hi !

I just heard about "hard reset" since i got my first ppc.

I don't know that does change a hard reset...Is it like formating your hard drive ?

Does it detete all calendar, contact list, programs, e-mail accounts, ringtones...?

The most important concern for me are my contact list, with pictures and notes, etc... what is the most appropriate tool to fully export them (in case ther are deleted after a hard reset)

Thank you very much !!!!