My '91 Corolla will not start. When I turn the key there is no clicking at all.

What is your question?

I can push start the car to get it started, but I cannot get it to start on it's own. All my friends seem to think it's my starter and I guess this model is notorious for that happening, but I just want to know why else it might do that. There is no clicking noise when I turn the key, and I know it is not my battery, alternator, or engine (all of those have been checked). Does anyone know what else this could be or if it is for sure the starter?