i just started modding i need to know the the colors and wolt of each color i don't want to be plugging a led into a 12v wire by accident thanks to anyone who helps me out
If you're also asking about the 20-pin Molex connector on the motherboard, that's a little complicated, partly because the colours are often different depending on the power supply manufacturer. You can find a diagram of an ATX power supply connector by doing a Google search for 'atx power supply pinout'. You'll probably need to disregard the colours in that diagram, though; they match the colours in my current power supply, but not my old one.
check out formfactors.org for detailed specs on standardised power supply interfaces, case dimensions, etc.