Scoobert "Scooby"-Doo is a Great Dane belonging to Shaggy Rogers, and mascot of Mystery Inc..
Scooby is brown from head to toe with several distinctive black spots on his upper body. He is generally a quadruped, but displays bipedal 'human' characteristics occasionally. Scooby also has opposible thumbs and can use his front paws like hands. He has a black nose and wears an off-yellow, diamond shaped-tagged blue collar with an "SD" (his initials) and has four toes on each foot and unlike other dogs, Scooby only has one pad on the sole of each of his feet (so that it was easier to draw in the Scooby-Doo Annuals).
Scooby-Doo and Shaggy share several personality traits, mostly being scared easily, but their friends (Velma Dinkley, Daphne Blake and Fred Jones) encourage them to go after the costumed villains usually with "Scooby Snacks", a biscuit-like dog treat or cookie snack (usually shaped like a bone or as shown in later versions of the cartoons Scooby's dog tag), though occasionally appealing to Scooby-Doo inherent loyalty and courage to take a more heroic stance.
In all iterations, Scooby has a speech impediment and tends to pronounce most words as if they begin with an "R", though most of the characters are able to understand him perfectly. His catch phrase, usually howled at the end of every episode, is "Scooby-Dooby-Doo!" or "Rooby-Rooby-Roo", sometimes followed by a quirky chuckle.