Reducing the number of HTTP requests in your page is the place to start.
Combine your background images into a single image and use the CSS properties to display the desired image segment.
Image maps combine multiple images into a single image.
The overall size is about the same, but reducing the number of HTTP requests speeds up the page.
Image maps only work if the images are contiguous in the page, such as a navigation bar.
Defining the coordinates of image maps can be tedious and error prone.
Using image maps for navigation is not accessible too, so it's not recommended.
Inline images use the URL scheme to embed the image data in the actual page. Combining inline images into your (cached) stylesheets is a way to reduce HTTP requests and avoid increasing the size of your pages.
Inline images are not yet supported across all major browsers.
tag: content 80% of the end-user response time is spent on the front-end.