At the start of season one, Clark Kent (Tom Welling) is a young man with superhuman abilities that's trying to figure out his place in this world after discovering he's an alien.  Throuhout the seasons, Clark Kent is slowly becoming more and more Superman, discovering his abilities as time goes on.

At the start of the show, Clark is friends with billionaire Lex Luthor, whose life he saved.  Of course, later on Lex would go on to become his nemesis before leaving the show

Clark has had an on and off again relationship with Lana Lang and in the latest seasons, fans have been hoping for a Lois and Clark finally.

Now, Clark works at the Daily Planet and is forced to meet all sorts of fun villains from the DC Universe.

Clark Kent Quotes

Clark: You know this is a crime scene.
Chloe: So?

Clark: The question is, how'd they get inside?
Pete: I don't know. Now stop channeling Chloe and come on.

Smallville Quotes

I'm about as real as it gets.

Chloe

Oliver: You've done a hell of a job keeping the world safe on your own, Clark. I'm here to help you now.
Clark: Good. Something tells me...soon the world will need all the help we can get.