Oekaki is a Japanese word that means "to doodle or scribble." This word is used most often in the English language as an internet term. On the internet, an Oekaki (oh-eh-kah-kee) is a message board system. The first impression of an Oekaki is a long page of posted computer art, mainly doodles that are saved to a server, with messages or posts next to or under the pictures.
Oekaki's mainly use the three most popular java applets: OekakiBBS, PaintBBS, and ShiPainter. They are each browser based programs that require no downloads (other than Java). They are used like any other art program and are usually much simpler than high end programs but more powerful than Microsoft Paint. Any device that moves the cursor (mouse, tablet, touch tablet, etc.) can be used to draw in an Oekaki, just like any other art program.
One of the neat things about Oekaki is the animation feature. When using an Oekaki, it is possible to choose the animation feature that allows other users to view the process of the drawing. There's also the ability to save a drawing without others seeing it and to be able to continue the drawing later.
Oekaki's can be used for any type of art, though the most popular style used is Anime, a Japanese style of animation. I have seen many different pictures ranging from fully realistic photo renderings to Anime styles to original styles. There is no limit to the quality of the images by using Oekaki, thus many artists like to also submit their works to other websites, such as deviantArt.com.