when I am in my car, every now and then my side airbag light will come on for a couple of seconds but then goes off.not sure why it does that but thought I would ask somebody that knows more than I do.

 

Search, it's been covered. Easy answer is normal.

 

is there somebody sitting in the passenger seat?
Read your car manual - if someone is leaning in that direction, it will temporarily disable the airbag or reduce it's ejection speed. Light just lets you know that is what is happening.

If not, may have a faulty sensor.