oekaki
お絵描き お絵かき掲示板 絵チャ おえかきびより お絵描き掲示板 binary_art
A drawing made with very simple tools, usually imageboard/bbs-embedded drawing software, with very sharp and thin lines.
Oekaki (お絵描き) is Japanese for "scribble" or "doodle". On the Internet, an Oekaki is a message board system that revolves around computer art created by a local art program. Oekaki artists often post their art to other websites, such as personal pages or free gallery websites, in addition to the original board.
A specific form is known as "binary art", the use of limited colors, no color blending, no antialiasing, and not low resolution, distinguishing it both from pixel art and general digital art.