S

Seed emails:
Email addresses placed on a list to evaluate the sending service; see what messages are being sent to the list, to track delivery rate, to evaluate the delivered message. Seeds may also be placed on Web sites and elsewhere on the Internet to track spammers' harvesting activities.

Segment:
The ability to select a subset of the list according to attributes of the recipients like demographics or previous open history.

Select:
A segment of a list determined by any number of attributes, such as source of name, job title, purchasing history and so on. CPM list renters pay an additional fee per thousand names for each select on top of the base list price.

Selective Unsubscribe:
An unsubscribe that allows a consumer to selectively determine which email newsletters they wish stop receiving.

Sender ID:
The new anti-spam standard being proposed by the major email providers. It combines two existing protocols - Sender Policy Framework and CallerID. SenderID authenticates email senders and blocks email forgeries and faked addresses.

Sent emails:
Number of email names transmitted in a single broadcast. Does not reflect how many were delivered or opened by recipients.

Server:
An infrastructure computer which stores, distributes, and relays email from one server to another in a network.

Shared server:
An email server used by more than one company or sender. Shared servers are cheaper since the cost to the broadcast vendor is spread among several users. In addition to reduce robustness, senders sharing a server risk being blacklisted if one of the other users infringes CAN-SPAM standards with the server's shared IP address. See Dedicated server.

Signature file or sig file:
A tagline or short block of text at the end of an e-mail message. Usually identifies the sender and provides additional information such as company name and contact information. Your signature file is a marketing opportunity. Use it to convey a benefit and include a call-to-action with a link.

SMTP:
Simple Mail Transfer Protocol, the most common protocol for sending email messages between email servers.

Snail mail:
postal mail.

Soft Bounce:
A soft bounce is the failed delivery of an e-mail due to a nonpermanent reason, such as mailbox full or unavailable server. Mail servers are configured to retry sending emails a number of times on receiving soft-bounce responses.

Solo mailing:
A one-time broadcast to an email list, separate from regular newsletters or promotions, and often including a message from an outside advertiser or a special promotion from the list owner.

SPAM:
Email messages sent to someone who has not opt-in or given permission to the sender.

Also known as "unsolicited commercial e-mail" (UCE), "unsolicited bulk e-mail" (UBE), "gray mail" and just plain "junk mail," the term is both a noun (the e-mail message) and a verb (to send it). Spam is used to advertise products or to broadcast some political or social commentary.

Spamhaus Block List:
A freely available and upto date blacklist created by Spamhaus.org, it is available at Spamhaus Block List. The SBL is a realtime database of IP addresses of verified spam sources (including spammers, spam gangs and spam support services), maintained by the Spamhaus Project team and supplied as a free service to help email administrators better manage incoming email streams.

Sponsorship Swap:
An agreement between email list owners, publishers or advertisers to sponsor each other's mailings or newsletters for free. See ad swap.

Spoofing:
The practice of changing the sender's name in an email message so that it looks as if it came from another address.

Split Testing:
Also known as a A/B split. When the list is divided into two parts, each of which is tested with a variation of the message.

Subject Line:
The title of the e-mail communication. The first line read by email recipients. The most important part of the email campaign copy; is the biggest influence on mailing open rates. Split testing is recommended to determine the best copy

Subscribe:
The process of joining a mailing list, either through an email command, by filling out a Web form, or offline by filling out a form or requesting to be added verbally. Same as opt-in.

Subscriber:
The person who has requested to join a mailing list. A list has both subscribers, who receive the message from the sender, and pass-alongs.

Suppression file:
A Do Not Email list that you run against any lists you plan on sending mail to prior to the send. Required by CAN-SPAM.