Cosplay is defined as “the practice of dressing up as a person from a film, book, or online game”. For example, if you’ve heard of the charity institution called the 501st Legion, this will appear familiar.
https://www.ccosplay.com/
This is a charity institution made of Star Wars fanatics wherein absolutely everyone wears a dressing up, trying to make it as realistic and accurate as viable. These people attend charity activities, together with the CHOC stroll, or associate with the Make-A-Wish Foundation.