The list functions in two basic ways. As a mailing list, where mail to the list is forwarded to all the list subscribers, and as a file source, accessed by sending specially formatted mail to request the desired files. There is a help text file available, that more fully describes the server and the commands that it accepts. See the section on How the List Server Talks to You. Anything sent here goes to everyone on the list, so be careful what you send, and please pay attention to proper list etiquette, described in the section, List Etiquette And You.
Nothing sent here is sent to the rest of the list membership.
If you send something that the list server doesn't understand, you'll get a help file back with more detailed instructions. See Subscribing and Unsubscribing below for subscription commands. Note that this is the address of a real person, and not a computer managing the list. Normal list admin questions should be sent here, but may take a day or so to be handled. A digest is simply several mail messages packaged into one large message.