Client-side image maps store the hyperlink information in the HTML document, not in a separate map file as do server-side image maps. When the user clicks a hotspot in the image, the associated URL is sent directly to the server. This makes client-side image maps faster than server-side image maps, because the server does not need to interpret where the user clicked. Client-side image maps are supported by Netscape Navigator 2.0 and later, NCSA Mosaic 2.1 and 3.0, and all versions of Microsoft Internet Explorer.