BrickColor

A BrickColor is a data type that defines a pre-set color. BrickColors are limited to a set of 64 colors allowed by Roblox, unlike s, which can be any color.

List of BrickColors
There is more than 1000 BrickColors that Roblox has stored, but only makes use of these 64 default colors.

Trivia

 * In an unknown date of 2017, s were changed to allow BrickColors or Color3s to set the color, instead of just BrickColors.