9. Server-side "Gateway" Programs

HTTP servers usually have a facility whereby programs or scripts resident on the server can be accessed by a remote browser. Such server-side executable programs or scripts are generally placed in a directory known as the cgi-bin/ directory (there may, in fact, be several such directories, with different names). This is named after the Common Gateway Interface protocol that is used to define how scripts can act as gateways between browsers and the server machine.

How these programs work is largely independent of the server you are using, although the configuration of the directories and the server can vary considerably from server to server. The following documents are written with an eye towards the NCSA family of servers. If you are using another server (Netscape/Microsoft/other) the general ideas should still hold, but the detail will be different. Consult your server documentation!

There are five sections to the gateway program documentation:

1. ISINDEX Searches
2. ISMAP Imagemap (active image maps)
3. cgi-bin script/programs discussion
4. FORMs
5. Server-Side includes (primarily NCSA and Netscape servers)
only)