Wat does these for?

[thaimonk]

Stepping Northbridge
Vdd
Vddr
Vdd mod
Vddr mod
Memory timings
Memory sync
Memory type & size
Northbridge
Southbridge
Cooling other components

do u have any link for me to read about these tihng? im kind of new to this BIOS and mobo stuff... just wanna learn more anyway... thanks in advance tho!

cheers