Email Deliverability Terms You Need to Know (part 3)

As with in any industry, those of us in the email deliverability world tend to throw out a lot of jargon. If you're new to the wonderful world of email, much of it may be jibberish to you. To help newbies and vertrans alike, I have put together a list of the top 80 email deliverability terms you should know. Below is part three of three (S-Z). Parts one (A-H) and two (I-R) have already been published, be sure to check them out!

Segment: The ability to slice a list into specific pieces determined by various attributes, such as open history or opt-in source.

Sender ID: The informal name for an anti-spam program that combines two existing protocols: Sender Policy Framework and CallerID. SenderID authenticates email senders and blocks email forgeries and faked addresses.

Sender: This is a generic term that refers to any company sending email to a large number of subscribers.

Server: A program or computer system that stores and distributes email from one mailbox to another, or relays email from one server to another in a network.

Simple Mail Transfer Protocol (SMTP): A server-to-server mail transfer protocol. Examples are Sendmail, Postfix, and Qmail.

Smart Network Data Services (SNDS): Offered by Windows Live Hotmail, SNDS provides data to senders based on actual mail sent to Hotmail subscribers. Metrics reported on include complaints, SmartScreen filter results, and spam trap hits.

Soft Bounce: Email sent to an active (live) email address but which is turned away before being delivered. Often, the problem is temporary, for example, the server is down or the recipient's mailbox is over quota. The email might be held at the recipient's server and delivered later, or the sender's email program may attempt to deliver it again. Typically, soft bounced emails can be identified with a 400 series SMTP reply code.

Spam: Spam is unsolicited email. Not all unsolicited email is spam, however. Most spam is sent in bulk to a large number of email addresses and advertises some product. Spam is an email message that you did not ask for and do not want from somebody you do not know, who wants to sell you something.

Spam Filter: A mechanism used to identify spam email and keep it out of the recipeint's inbox.

SpamCop: A blacklist and IP address database, formerly privately owned but now part of the email vendor Ironport. Many ISPs check the IP addresses of incoming email against SpamCop's records to determine whether the address has been blacklisted due to spam complaints.

Sender Policy Framework (SPF): A protocol used to eliminate email forgeries. A line of code called an SPF record is placed in a sender's DNS information. The incoming mail server can verify a sender by reading the SPF record before allowing a message through.

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

Sender Reputation Data (SRD): Used by Microsoft Live Hotmail and MSN Hotmail, SRD is a collection of non-biased responses from feedback loop participants over time. Along with other sources of reputation data such as the Junk Email Reporting Program (JMRP), the Windows Live Sender Reputation Data helps to train and improve the way Microsoft's SmartScreen technology properly classifies messages based on email content and sender reputation.

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.

Subscriber: The person who has specifically requested to join a mailing list.

Suppression File: A list of email addresses you have removed from your regular mailing lists, either because they have opted out of your lists or because they have notified other mailers that they do not want to receive mailings from your company. Required by CAN-SPAM.

This is Spam Rate: The rate of emails that are marked as junk/spam by recipients, typically expressed as a percentage over total number of emails delivered.

This is Not Spam Rate: The rate of emails that are recovered from the junk/spam folder by recipients, typically expressed as a percentage over total number of emails delivered.

Throttling: The practice of regulating how many email message a broadcaster sends to one ISP or mail server at a time. Some ISPs bounce email if it receives too many messages from one sending address at a time.

Transactional Mail: Transactional messages are defined under CAN-SPAM as any email "facilitating, completing or confirming a previously agreed upon transaction." Unlike commercial messages, transactional messages aren't required to have a U.S. Postal Service address or an unsubscribe link.

Unknown User: Bounce error code generated by an ISP when an email address is not registered in its system.

Whitelist: A list of contacts that the user deems are acceptable to receive email from and should not be filtered or sent to the trash or spam folder.

X-header: A user defined header element that is injected into the header portion of an email message.

Have a different definition for one of the terms above, or did I miss an important term?  Please comment below!

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