what's the difference between reindeer and deer

Reindeer are a subspecies of deer that are native to the Arctic regions of the world, including the northernmost parts of North America, Europe, and Asia. They are distinguished by their larger size, thicker fur, and longer legs and feet than other types of deer. Reindeer are also known for their distinctive antlers, which can grow up to three feet long and are used for defense against predators and for competing with other male reindeer during the mating season.