What's the difference between iphone 5 and the 5c and 5s?

Is there a big difference? I was thinking of getting the 5c but I don't want to if there's only minor differences. I don't know much about phones so that's why I'm asking but I do have the iphone 4.

Added (1). I don't know much about phones but I do know that the iPhone 5 has Siri

I'm pretty sure the difference is that 5 has no letter after it and 5c and 5s have a 'c' and an 's' after it respectively.

The iPhone 5 has no siri and is basically JUST an intro to the "longer phone"
I hate it so don't buy it.
The 5c stands for Color. It comes in red, blue, green, white, and yellow. Its my favorite buy and it does include siri. It's also only 99$! Don't worry about the plastic case.
The 5s is the most advanced at 199$.It has a finger censored home button, which makes it "special",
Buy the 5c. It's cheap, colorful, and everything is included.

If you have iPhone 4 and you want to upgrade, get the iPhone 5S which will be a perfect upgrade for you.

Are you guys are still arguing about that ***? They are all the *** same!

There are a few differences between all three. Some are comparable between two versions, but some are different across all three devices. I wrote an article between all three: http://whatsthediff.net/featured/whats-the-difference-between-iphone-5s-and-5c/