Co-creator of The Simpsons, Sam Simon, has died at the age of 59 after a long battle with cancer.
The Simpsons showrunner Al Jean tweeted "Just heard terrible news of death of @simonsam. A great man; I owe him everything."
When Simon was diagnosed with cancer in late 2012, he promised to leave his $100 million fortune to charity and established the Sam Simon Foundation as well as buying zoos and circuses to free animals.
Here's a gallery of some of the clever signs that have been on the show that you may have missed!