The Yorkie traces to the Waterside Terrier, a small longish-coated dog, bluish-gray in color, weighing between 6 and 20 pounds. A breed common in Yorkshire since early times, the Waterside Terrier–crossed with the old rough-coated Black and Tan English Terrier and with the Paisley and Clydesdale Terriers–was brought to Yorkshire by the Scotch weavers who migrated from Scotland to England in the middle of the nineteenth century. All these breeds were bred together to make what is now known as the Yorkshire Terrier. They should not weigh more than 7 pounds. They are one of the most popular dogs. I think they are the #1 most registered dog with AKC now.