We tend to immediately think of rats when anyone mentions rodents. Rodents make up the largest order of mammals. They include beavers, voles, mice, dormice and squirrels. Rodents have two incisors which must be kept short by gnawing as these incisors don't stop growing!
There are a great many primates in the world, but here in Great Britain we only have one. If you are not sure which one it is, go and look in the mirror!