Collies are of two types, the Smooth and the Rough coated types. Lassie is the Rough coated Collie characterized by short hair. Twice a year, their coat sheds quite heavily while for remaining parts of the year, their shedding is quite normal.

Both types love to mix up, socialize, and make great house pets. It is easy to train them as they are very sharp, intelligent and quick in learning things and intelligent. They are obedient and quickly pick up the training sessions as they are eager to make their trainers and owners happy. They are not aggressive, but can be good watch dogs if trained properly. They are very sensitive and do not respond to corrections or harsh training. One needs to be firm, yet not harsh or else they can stop co-operating. Normally they are gentle animals, but as the need arises wherein danger is apparent, they can be fearless and go to any extend to protect and defend their owners.

Both types have the uncanny ability to understand the needs of the humans and their love for the humans is very strong. They go along well with humans, and easily bond and socialize with them. Hence, they are a good choice for assisting the handicapped like blind. They can pull on with anyone be it human or animal. They also pull on well with children. If left free or on their own, they tend to chase anything like cars, bikes, children or joggers; due to the natural inbuilt instinct of herding. They require company and if left alone for long, become restless, get bored, and shall bark constantly.

Both types diet are common. It consists of five cups of dog food (dry) with minerals and vitamins included. They can also have a one and half cans to a maximum of two and half cans of good quality meat product.

The smooth collies height varies between twenty-three inches to a maximum of twenty-six inches. It weighs between fifty-five pounds to a maximum of seventy-five pounds. The Canada and United States collies are larger in size. They are longer than they are tall. The face and eyes has a soft and sweet expression and are therefore considered as show dogs. Their undercoat is extremely thick, dense and straight with stiff and rough outer hairs. The outgrowing hairs can grow to a length of two to a maximum of three inches long. They need to be brushed regularly due to the hair length and the roughness of the outer coat.

The Rough Collies coat is double layered and do not require much care like the smooth one except for the frequent brushing. Their coats are of varied combinations of white and sable.