Oekaki

Oekaki (Japanese お絵描き, "drawing" or "doodling") is an in-browser drawing tool on 2swagg's /oc/ board. It lets you paint an image right on the site and post it as your reply or thread, instead of uploading a file you made elsewhere.

Oekaki boards are an old imageboard tradition, going back to Japanese boards in the early 2000s that ran applets like Shi-Painter and PaintBBS. Keeping one on /oc/ ("Internet Meme Machine") fits that board's original-content focus.