1, A costume, basically. But more complex and casual, meant to reflect something called a "Fursona"- aka an alternate animal humanoid of that person that they have made, or an animal humanoid in general. These can get very expensive, and are VERY hard to make. Next time you see a person in a fursuit and they say they made it, at least act impressed. Cosplay is very hard to make, people!!
2, A person who has an alternate version of themselves as an animal humanoid, or simply a humanoid animal. There are some (like me) who would also think it would be cool to have animal ears and a tail, or the ability to shift into these animals, and embrace that through costumes.
And 3, Because some of us can be so embarrassing and cringe. :( ALSO, because people are ignorant and hate change.
I hope this answered your questions, and have a wonderful day. <3
