
Supercheap had superforce driving lights in various shapes and sizes for 10 bucks the other day. I missed out but it got me thinking again about the crap EA81 lights and my desire to put perhaps some little 40mm halogen cateyes in the bumper.
I must admit i had the idea that it would be as simple as buying a switch from D*cksmith and some wire and hooking the lot up to the battery.
A mate suggested there were legalities involved and you should hook them up to your high-beam switch, and that i needed something called a 'relay'

i've heard the term before and i figure it has something to do with not running the battery flat or short circuiting anything.. but other than that i don't have a clue.
Could somebody give me a quick run down of the steps for installing lights that just come with two wires and no info/instructions?
Does the extra wire need to be any special type? What's a relay? Yes, I have seen the wiki but it doesn't have quite enough info to make me confident in buying anything yet.
Thanks for any help,
Dave