Pedobear gained iconic status through 4chan, but he wasn't always associated with CP. On 2ch, he was simply an ASCII bear.

Befitting of its "anything goes" reputation, 4chan's /b/ is known for its fascination with street brawls, especially when the underdog wins. So was the case of Casey Heynes, an Australian student who slammed a bully into the ground after getting harassed in the schoolyard.

Rule 20: nothing is to be taken seriously.

Credited by 4chan founder m00t as the father of the Rickroll, this duck on wheels revolutionized lulz in 2005.

These images are used to express a specific emotion in a similar fashion to their plain text ancestors: the emoticons.