What does the SRS warning light mean on a Honda Civic?

I have a 96 Civic. Air bag warning light came on several days after I had been hit from behind in an accident. Cleared the code such that the light went off for a while. Came back a couple of weeks later.

Eventually my battery died and I had it replaced. Once the air bag (SRS) light was turned off, it never came back. And it has been over a year now. Point is, a weak battery can be responsible for this light coming on when the SRS unit is perfectly OK otherwise!