Furry is the commonly-accepted name of a branch of the Science Fiction
Fandom focusing on animals with humanlike characteristics, or anthropomorphic
animals with abilities to do things like walk and talk.
Sometimes conventions are held for people in the fandom
to go meet each other. While some of them like to wear animal-related accessories (like fake ears and tails) and others make elaborate costumes to look like there ideal furry character, this is by no means a requirement.
There are a lot of furry artists and writers as well, who draw and write about anthropomorphic animal