Macbook backlight issue

I have a macbook that was purchased in early 2008 so is now out of warranty.
The other day the backlight on the macbook stopped working completely, I've heard there are a variety of reasons for this happening. It happened to my brothers who bought his at the same time but apparently his was because of a crimped cable, because if you tilted the screen to a certain angle it would turn on. This wasn't the case with mine
Mine would just turn on for about 5 seconds on start up and then go black. I managed to set up an external monitor by shining a torch on the screen to see what was going on on the desktop.
Today though the screen on my macbook completely returned to normal, and I was wondering what people on here thought the most likely cause of this problem was and whether or not I can do something to stop the screen blacking out completely in the future.
Any help would be much appreciated! Cheers

Welcome to the Mac Forums.

Two possibilities: Either the inverter board or the inverter cable. Actually, there's a third - the CCFL backlight tube itself, however, changing one out is difficult. Apple recommends changing the entire LCD if the CCFL is bad.

Go to iFixit: The free repair manual for parts and instructions.