Extracting Firmware or Bios

I don`t know where other place to ask so here`s the place.
I read in the news bout hardware hacking such as Bios and the Firmware hacking. And i'm curious just how exactly do we extract the firmware information ? I mean it`s ll embeded into a rom chip right so how the hell we extract it?

>>2
So how the heck u extract it if its  a ROM chip

>>3

If it`s a flash mem how the heck i extract it