1997 F250 5.8 Just clicks

I am not sure what happened to my truck? When I tried to start it all it would do is click. I am not sure if it would be a relay or maybe the starter going bad? Any help would be great. Cylinoid?

Does it click a lot rapidly or does it click once and stop

does it click once and the light dim??? if so it's probably just a battery connection. try pouring coke on the terminals and wiggling the cables u may laugh but believe me it works... the acid in the coke eats the corrosion.