To make this, you need to create
a series of "frames", then use a program to compress them into one
GIF. See:
You can choose one of the colors in your image to become "transparent". If you do, the background will be visible through your graphic. To do this, you need to save the GIF in a special format called "GIF89a". On the MAC, use Transparency, or the plugin for Photoshop called PhotoGIF.
Interlaced GIFs
Interlaced GIFs load layer by layer, with each new layer adding to the image resolution. Interlaced graphics can be created with GraphicConverter and GIFConverter, available here.
Animated GIFs
These are becoming very common on the web...
To make this, you need to create
a series of "frames", then use a program to compress them into one
GIF. See:
Image maps
Image maps are navigational tools that can take you from your current location (a web page) to another. UT's Homepage has an example of an imagemap.
Most browsers support server side image maps, which rely on a CGI script and a configuration file to link the coordinates with the areas in the image and the URL. Obviously, this implies additional work for the server.
Client side image maps are becoming more popular, and are parte of the new HTML 3.2 standard. Netscape Navigator, Microsoft Explorer, and Spyglass Mosaic all support client side image maps. You can get detailed info on this reading the Client side image map specs.
For an example, click here, and take a look at the source code! To create an image map, you will need a program to help you map the coordinates on your image. If you're working with a few simple rectangles, use Photoshop. Otherwise, use MapEdit for Windows or WebMap for Macintosh.