I have seen blocks like these:

go back ( 99) layers

So, I wanted to ask, what is a layer?

Hello! Please do not post copies of your own topics.

Think of layers like the layers when you edit your costume in vector, every object has a layer. Objects with higher layer are at the front, objects with lower layer are at the back. You first the the object at the front then the object behind it.

nerdiebirdy wrote:

Hello! Please do not post copies of your own topics.

Sorry, but it helps if more people are able to anwser my question

If several sprites are on the screen, Scratch has to have a system of deciding which sprites will be drawn in front of other sprites when they overlap.
If there are 5 sprites in a project, they are assigned to 5 different layers which determines their order from front to back.

The layer blocks let you change the layer order of sprites.
eg.

go to front


go back (2) layers