CSS sprite generator
I wrote this post a while back. The content can still be relevant but the information I've linked to may not be available.
CSS background image position properties allow the use of one 'master' image that contains multiple component images instead of separate images. The technique is known as CSS Sprites and it has the advantage that rollover images appear instantly because 'they' have already been downloaded as part of the master image. This means that there's no need to use JavaScript to preload images. The use of CSS Sprites can also improve website perfomance because there are less HTTP request made to the server.
At first glance, this may seem like more work because you need to create the master image in your favourite image editing programme and then write the CSS rules ......or you can use this neat CSS Sprite Generator which will combine the images and generate CSS rules for you. I know which method gets my vote.
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