AC type approach lighting is suitable for category II low visibility operations. The kead-in lights are at least 2400' of white bars, with the last thousand feet flanked by red bars, and with green threshold lights. This is a very common system and there is a great picture of it here. I'll remember AC lighting by thinking of the three columns of light in the last thousand feet before the threshold as "A B C".
In the picture you also see lights on the runway itself. There's a line of lights running right down the middle of the runway, that's CL, runway centreline lighting. The CL lights are white at the beginning of the runway, alternating red and white when there is two to three thousand feet of runway left, and all red in the last thousand feet of the runway. The picture also shows a wide bar of white lights either side of the centreline for the first 3000' of the runway. Those are TDZL, touchdown zone lighting.
By the way, if you go and look at the approach lights you will see that each one is a heavy duty lamp up on a pole. The poles get longer as you get further from the threshold. Often the lights extend beyond the airport fence, so you can walk up to them and look at them. The lights in the runway itself are recessed, and do not stick up at all, so it's not bumpy landing on them. It can be distracting, though, when you're used to hicktown runways with only paint and coyotes on them.
Reader Blake provided another picture of AC lighting, here.