CSS Sprites is very effective way for improving site performance, it reduces number of HTTP requests. CSS Sprites method combines all of your small images into 1 images. If we done correctly then his will lower web page load times and actually help your SEO efforts.
CSS sprites are simply a method used where you get all your small images used for a website and make 1 image out of them, then use CSS to select certain parts to display in the correct place.
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