NCSA httpd allows you to write server scripts, which are executable programs which the server runs to generate documents on the fly. They are easy to write and can be written in your favorite language, whether it be C or REXX.
These scripts can be used for a number of purposes.
If you are using a browser which supports HTML forms, like Mosaic 2.0 for X, you can create scripts to handle form requests.
For example, let's order a sub.
If you are familiar with the PH system, you can look a person up in the phone book.
If you are using a browser which supports it, you've probably noticed that image mapping is a fun feature. NCSA httpd lets you create your own maps.
Below is a picture of some ray traced fish. Try clicking on different areas of the picture and see what it does.