Additional info about horses

I'm no expert but google says

F = Filly - A female horse or pony under 4 years of age.

G = Gelding - A male horse or pony of any age that has been gelded (castrated).

C = Colt - A male horse or pony under 4 years of age that has not been gelded (castrated).

Sound about right?

Thank you so much Maddox!
I've tried Google myself, but couldn't find anything, so you are by far a better searcher!

Your welcome, I should also meation

Mare - A female horse or pony that is 4 years or older.

From http://www.equine-world.co.uk/about_horses/equine_gender.htm

but on wiki there is a line that says
"In horse racing, the definitions of colt, filly, mare, and stallion may differ from those given above. In the UK, Thoroughbred horse racing defines a colt as a male less than five years old, and a filly as a female less than five years old.[18] In the United States, both Thoroughbred racing and harness racing define colts and fillies as four years old and younger.[19]"

http://en.wikipedia.org/wiki/Horse

So now i'm not so sure