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

Lex: The two theories seem to be I either ran the plant into the ground through incompetence or did it deliberately so that I can go back to Metropolis.
Clark: Your dad already offered you a job in Metropolis - just tell people the truth.
Lex: Then they get stuck with the incompetence rap. Being reviled is the lesser evil.

(after catching his parents "counter macking") I did not need to see that!

Clark

Smallville Quotes

I'm about as real as it gets.

Chloe

Clark: My father says you learn more about yourself when you lose.
Lex: What'd you learn?
Clark: That I'm not destined to be a politician. You need two different personalities.
Lex: You don't need to be an elected official to change the world, Clark.
Clark: Have you ever thought about getting into politics?
Lex: Someday I'd like to be president.