The Chihuahua is a tiny little dog with a great big personality. Some of them weigh as little as two pounds!
They are considered 24th most popular breed by the AKC. I can't prove their ranking, but I do know alot of people who have them. When I was a child, we had one named "Cheetah". I once saw her chase a Doberman Pinscher out of our back yard. Fearless!
With my business, I see quite a few chihuahuas because they get cold so easily. Small dogs with smooth coats need help staying warm. Some chihuahuas have long coats, but they still get pretty cold. Plus people love to dress them up!
The breed is named after Chihuahua, Mexico, where they originated. It is believed they descended from the ancient Techichi, dogs of the Toltecs prior to the 9th century. Evidence from 300 B.C. show the Techichi was present in local culture. Although the exact history is a bit fuzzy, it looks like they've been around for a LONG time!
They are popular in current culture, as evidenced by this Taco Bell ad. They are very portable and ride in dog purses pretty often, Think Paris Hilton.
Per the AKC, "Inside each little Chihuahua is a miniature king or queen ready to rule their realms, so they need to be taught what is acceptable in human kingdoms." Remembering Cheetah, they can be naughty little things, but loveable.
Due to their sassy personality and small size, they often don't tolerate households with small children very well. They don't need tons of exercise so Chihuahuas do well in small apartments or other situations that don't provide alot of activity. They can get to be set in their ways, so socialization is a plus.