The special colors are slightly different shades from the basic colors.

This is especially fun if you're looking for something a little different from your standard colors.
This works particularly well for fidget toys, small gifts, or objects that are mainly meant to look fun.

For strong parts that need to handle a lot of force, such as coat rack hooks, you're better off looking for something else. Luckily, the filament type PLA works on almost every 3D printer!