This extension overrides all fonts on webpages with the OpenDyslexic font, and formats pages to be more easily readable.
Your brain can sometimes do funny things to letters. OpenDyslexic tries to help prevent some of these things from happening. Letters have heavy weighted bottoms to add a kind of "gravity" to each letter. You are able to quickly figure out which part of the letter is down because of this feature. It aids in recognizing the correct letter, and sometimes helps to keep your brain from rotating them around. Consistently weighted bottoms can also help reinforce the line of text. The unique shapes of each letter can help prevent confusion through flipping and swapping.
The OpenDyslexic Firefox Add On is perfect for people looking for a more readable content on the web.