I am making a project and I want to use the pen category in it. But I can't understand what does all the pen blocks mean (clear, stamp, pen down, pen up, etc.).

Well, this forum should be in help with scripts, but nevertheless, I can explain.

You start with “pen down”, that leaves trail (a line, presumedly drawn by a pen) when your sprite moves. But you need your sprite to move. Pen up just *picks the pen up* and stops leaving the trace.

Stamp stamps an image of your sprite.

Clear clears all pen marks.

It's hard to explain in the forums, but here's a link to a tutorial on pen blocks.

Hope this helps!

It does! Thanks!