What is the difference between server-side and client-side image maps?

server-side and client-side. In the server-side method, when you click an image leading to multiple links, you are actually invoking a cgi-bin program. The program typically reads a separate map file that tells the program where to go, depending on what part of the image you are clicking. The program returns the destination to the web browser, which then opens the page. The imagemap is called "server-side" because the web browser must contact the remote host to find which site to contact.

Client-side imagemaps, by contrast, do not require a cgi-bin program to function. The imagemap is actually an HTML construct that can be contained on the same page as the clickable image. Rather than requiring the program on the remote host to determine what site to access, the web browser itself associates regions of the image with the appropriate sites. The browser, rather than the remote host, interprets the imagemap.