What Is The Difference? It’s actually pretty simple.
The main difference is whether it’s one piece or many!
A sticker has no masking paper, which means there is no extra layer on top of the vinyl film to help apply it and/or hold it together, because it’s done as a single piece. Masking paper is unnecessary with stickers because they are printed and cut as a single piece that holds itself together.
A decal does have masking paper on it because it is usually cut into multiple pieces all making up the one decal. The mask allows the decals piece to stay together when removing the backing paper, allowing you to apply the decal as if it were one single piece.