The miniature and giant schnauzer are both derived from the standard schnauzer, a German breed that has existed for centuries. However, they also have key behavioral differences that have led the American Kennel Club to classify them as three distinct breeds, each with their own temperament and personality traits.
Schnauzers have appeared throughout the ages in paintings from such artists as Albrecht Durer and Rembrandt. This breed appears to have begun as a cross between the black German poodle, the gray wolf spitz and the wirehaired pinscher. Small standards were then crossed with the affenpinscher, and possibly the poodle, to create the miniature schnauzer, while larger members of the breed were crossed with the Great Dane and the Bouvier des Flandres to create the giant schnauzer.
Standard schnauzers are friendly and intelligent dogs. They're highly social, love children and generally do best in a family. They are fiercely loyal and protective and have a long history as working dogs in Europe, capable of helping with various farm-related tasks. They also make good guard dogs thanks to their territorial nature and tendency to bark at strangers. Like many intelligent breeds, the schnauzer can be strong-willed, so training should begin as early as possible to combat any stubborn streaks. This breed also possesses a lot of energy and needs to be able to burn it off with plenty of exercise.
Miniature schnauzers share many of the same personality traits with standard schnauzers, but there are a few key differences. Their small size, boisterous nature and tendency to bark at strangers and doorbells might make them seem yappy and high strung. Although they tend to do well with children, these dogs were bred to hunt small, furry creatures and should be supervised around small children. Similarly, they probably shouldn't co-exist in a house with pet rodents or birds and should be watched carefully around kittens. They do, however, tend to get along well with other dogs. While miniature schnauzers make good family pets, they have a tendency to single out a favorite person.
The giant schnauzer shares traits with both the standard and miniature schnauzers. Like the standard, the giant is intelligent, energetic and protective of family and children. However, like the miniature schnauzer, the giant should be supervised around babies and toddlers. These dogs were bred to work and are happiest when they have a task to focus on. They also require significant exercise, playtime and mental stimulation. Like all schnauzers, the giant is headstrong and should receive obedience training at a young age.