These are the clothing items in ROBLOX.
T-Shirts[]
T-Shirts were released in 2007/2008. They are almost like shirts, except they are just a picture on the front of your torso only. Any user can create T-shirts, They were used as givers for game perks until around 2012/2013 where Game Passes came about.
Shirts & Pants[]
Shirts & pants were released in 2008 and were usually just used to customize avatars, and some shirts can put optical illusions on your avatar. Same goes for pants. Any user with Builder's Club can create them.
Hats[]
Hats released around 2007. They are usually the most made clothing to this day, and there are limited hats that have prices set by the item owners. Same with gear and faces. Only ROBLOX administrators can create hats.
Faces[]
Faces released in 2009. Only ROBLOX administrators can create faces.