The community of Transformers fans is referred to as a fandom. While the term technically encompasses any group of kids coming together to talk about Transformers in a sandbox, it is commonly used to refer to the people from college-age and up who participate in the online fandom
The fandom has long played a role in the history of the franchise. Most notably, BotCon was their Mardi Gras, an official convention geared almost totally to adult fans.
In the eary days, fans coined the term Transfans to refer to themselves ,along with the occasionally-used female variant Transisters. However, the term has generally fallen out of vogue over the years, and most today simply refer to themselves as "Transformers fans".
Fans tend to wear handmade or store bought costumes .Often, store bought outfits look much better, but they prefer to wear handmade costumes, it looks more authentic and realistic.