Terrier (from the French word terrier [tɛʁje], meaning "burrow") is a type of dog originally bred to hunt vermin. A terrier is a dog of any one of many breeds or landraces of the terrier type, which are typically small, wiry, game, and fearless. Terrier breeds vary greatly in size from just 1 kg (2 lb) to over 32 kg (71 lb) and are usually categorized by size or function. There are five different groups of Terrier, with each group having different shapes and sizes. Source: https://en.wikipedia.org/