Mail header style
With a "regular" subscription, you receive individual postings immediately, as they are processed by LISTSERV.
With a "digest" subscription, you receive larger messages (called "digests") at regular intervals, usually once per day or once per week. These "digests" are collections of individual list postings. Some lists are so active that they produce several digests per day.
Digests are a good compromise between reading everything as it is posted and feeling like the list is clogging your mailbox with a multitude of individual postings.
There are three digest formats: a "traditional", text-only format; a MIME format, which (with mail clients that understand MIME digests) "bursts" the individual messages out of the digest so that you can read them separately; and an HTML format, which requires an HTML mail clients.
With an "index" subscription, you receive short "index" messages at regular intervals, usually once per day or once per week. These "indexes" show you what is being discussed on the list, without including the text of the individual postings. For each posting, the date, the author's name and address, the subject of the message and the number of lines is listed. You can then download messages of interest from the server (the index contains instructions on how to do that).
An index subscription is ideal if you have a slow connection and only read a few hand-picked messages. The indexes are very short and you do not have to worry about long download times. The drawback of course is that you need to reconnect to order messages of interest from the server.
You can choose to have the index sent to you in either a traditional format (plain text) or in HTML format with hyperlinks.
"Full" mail headers (normally the default), containing Internet routing information, MIME headers, and so forth.
"Full" mail headers (like the default) except that a "subject tag" is added to the subject line of mail coming from the list. If there is no subject tag defined in the list's configuration, the name of the list will be used. This can be very useful for sorting and filtering mail.
These headers are similar to the normal LISTSERV-style header except that Internet routing information and MIME headers are removed.
Dual headers are regular short headers followed by a second header inside the message body. This second header shows what list the message is coming from ('Sender:'), the name and address of the person who posted it ('Poster:'), the poster's organization, if present, and the message subject. Dual headers are helpful if your mail client does not preserve the original return e-mail address.
This option selects sendmail-style headers, i.e. an exact copy of the original, incoming mail header with the addition of a 'Received:' line and of a 'Sender:' field. Some technical people prefer this type of header.
LISTSERV will not send any acknowledgement at all when you post to the list. This is probably not a good setting unless you really do not want any feedback from LISTSERV as to whether or not your posting was received and distributed.
Typically this is the default setting, although it can be overridden by the list owner. If you choose this setting, LISTSERV will send you a short message whenever you post to the list, confirming the distribution of your message and telling you how many people it was sent to.
Some people prefer this setting over the short acknowledgement message. It tells LISTSERV to send you a copy of your own postings, so that you can see exactly how it appeared on the list (useful if you are behind an unreliable gateway or firewall).
This option toggles the receipt of mail from the list. You may want to disable mail delivery if you will be away from your mail for an extended period of time.
This option conceals you from the list of subscribers shown by the REVIEW command. Note that the list owner and the LISTSERV administrator can always get the complete list of subscribers, regardless of this setting. Nowadays, most lists are configured so that only the list owner can use the REVIEW command, but some lists still allow subscribers to get a listing of all the other participants.
For lists with topics enabled (if the Topics: section of the form is not visible, topics are not enabled), this section allows you to subscribe or unsubscribe to all, some, or none of the available topics.