The term "bulldog" was first used around 1568 and might have been applied to various ancestors of modern bulldog breeds.
This information was taken from Wikipedia.

Bulldogs have a long list of traits that contribute to their many health issues. Their short muzzle makes it hard for them to breath and causes them to snore while they're sleeping.
This information was taken from Wikipedia.

The Bulldog comes in a variety of colors and ideally has a smooth, short coat. The colors, in order of desirability, are brindle (especially red brindle), red (like a chestnut horse), white, and fawn (often with white markings on any color, or piebald).
This information was taken from Wikipedia.