What is a Whippet?

When people ask me my hobbies, I always say that I show dogs. The next question is always the same: What kind of dogs? I then reply by saying that I show whippets. And then eighty percent of the time I get this question: What's a whippet? Regretfully I always respond by saying, they are a small greyhound, but in reality, they aren't completly like a greyhound at all.
A whippet is a small sighthound. Sighthounds are dogs that hunt by sight, and chase their game down. Because of this, sighthounds are among the fastest dogs in the world. The size of the sighthound depends on what they hunted, for example the Scottish Deerhound is a 85 to 110 pound dog, that hunts deer, where a Whippet that ranges from 18 up to 30 pounds hunts rabbits.
Like there are differences between sighthounds, like the deerhound and the saluki, there are differences between the greyhound and the whippet. They do look more alike than the other sighthounds, but the gryhound is much larger, and has a flatter topline. Also, whippets have longer necks for their size and a whippet's color in immaterial, where there are standards for the greyhound.
This is only a small amount of imformation on what a whippet is, but you can see why I don't go into complete detail when someone asks me, what they are.