If you activated the new Inbox Tabs then after a while you find yourself not liking them that much and would like you old priority inbox back, this is what you need to do.
If you want to put your video files online using HTML5 then it's recommended to have three different formats for a full browser support. Those formats are mp4, ogv and webm.
If you found yourself in a position where you wanted to crop a certain photo into a perfect square but you just couldn't figure it out how, than this tutorial is for you.
Very useful Javascript feature that can prevent a user from losing the data they are entering in an entry field or text editor in case of unintentional leaving of a page.