Why does it take so long for my mouseover images to appear?
The first time you hover the mouse over an image, the browser has to download the new image from the server, which can take time. The easiest way to reduce that time is to use smaller images. If that’s not practical, you can also “pre-load” all the images. This means that the images are loaded into memory when the page is loaded, so they appear immediately when the user places their mouse over the image. See my third mouseover tutorial to learn how to pre-load images.