Collie is a name given to several herding breeds originated in Britain, although in the United States that name usually refers to the specific breed called Rough Collies. But, collie herding dogs include several other breeds, such as, for example: German Coolie, Australian Collie, Smooth Collie, Farm Collie, Bearded Collie, and Border Collie, among others.
Collies usually belong to the medium sized dog category, having an average weight which ranges between 10kg and 25 kg. The fur varies from one breed to the other: it can be, for example, long, short, smooth, or bushy. Their colors vary as well: collies can be black, red, black and tan, red and tan, or dark brown, and often these colors are combined with white.
The temperament of working collie dogs usually is very energetic. These dogs need a lot of exercise, and usually they won't get tired easily. Therefore, these dogs require space to run and spend energies, and are not suitable for living in an apartment or small place unless they can have a space for exercising as well as go for long walks in a daily basis.
Collies usually are very smart and affectionate dogs. They are very
loyal to their family and, although they tend to be very social and
friendly, they are careful with strangers, factors which often make
them good guardians.