There are three species of bears in North America - Black bears, Brown bears, (includes popular - but not genetically different subspecies designations of Kodiak, Grizzly and Coastal Brown bears) and Polar bears. (the only North American species I've never seen in the wild).
To add some confusion, Black bears can be brown, blonde, or cinnamon-colored, and are the smallest species of North American bears. Polar bears are the largest.
All are fascinating to watch!