CSS Sprites技术不新鲜，早在2005年 CSS Zengarden 的园主 Dave Shea 就在 ALA 发表对该技术的详细阐述 。
通过CSS Sprites方法将多张图片组装成单独的一张图片，可以有效减少HTTP请求的次数。Yahoo的YUI也使用了，Google也使用了它：
CSS sprites allow you to create a single file that contains all the images laid out in a grid, meaning only a single image and only a single server call, with roughly the same file size because the empty space is compressed. In that file, you will place all individual "sprites" that make up your interface separated by enough space that they don’t start running over each other. You’ll then set the background position (using negative values to move the background up) and include enough space around each sprite so that only it appears in the background of the element, effectively masking the rest of the sprite images
更多信息可以看看：http://hi.baidu.com/vivaid/blog/item/d9feb064842b43f3f736541e.html
