My '94 Saturn SL1 wont start?

All of the electrical works, I replace the battery myself and I'm pretty good with cars as far as installation (I took auto shop lol). All the lights, radio, dashboard lights, even the automatic seatbelts work. i turn the key and i hear a very soft buzzing noise. Its not that loud and it doesnt happen every time, about every 3 times i turn the key it makes the noise. I think it might be solenoid, but to be honest i have no idea lol.