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.
CSS is a mighty powerful language for shaping your web objects. You will learn to create a two versions of a web button, one with and other without a transition.
If you find yourself in a situation when you need to list your Mac specs or you just want know if you really got what you paid for, this is how you find them out.
Some websites overlay their photos and images with another blank image. But there's an easy way to download those pictures if you are using Google Chrome browser.