lights on bottom

[wedgemoose]

Again, I am totally new to Android. And i absolutly LOVE it. this phone is amazing!!!!!!!! i may be missing something but it seems my lights on the bottom shut off and don't turn back on (the ones over Home-Menu-back-search). I noticed last night. they did come on after i did something but don't know what it was. and then off again even while I was using them navigating in the market.

is this how it is and I just don't know? or is there a setting I'm missing

thanks in advance