Email Deliverability Terms You Need To Know (part 1)

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 one of three (A-H), stay tuned for parts two (I-R) and three (S-Z) over the next couple of weeks.  At this rate, you'll be an old pro by Thanksgiving!

Above the Fold: The part of an email message that is visible without scrolling. Material in this area is considered more valuable because the reader sees it first. This is originally a printing term used for the top half of a newspaper above the fold. Unlike a newspaper, email fold locations aren't predictable. Your fold may be affected by the users' preview pane, monitor-size, monitor resolution, and any headers placed by email programs such as Hotmail, etc.

Authentication: Authentication is the process of attempting to verify the digital identity of the sender of a communication. In email marketing, there are four main types of authentication: Domain Keys, DKIM, Sender ID, and SPF.

Bacn: Email that has been subscribed to and is therefore not unsolicited (like email spam is), but is often not read by the recipient for a long period of time, if at all. Bacn has been described as "email you want but not right now." Bacn differs from spam in that the recipient has signed up to receive it. The name bacn is meant to convey the idea that such email is "better than spam, but not as good as a personal email".1

Blacklist: Lists of IP addresses that have been reported and listed as "known" sources of spam. There are public and private blacklists. Public blacklists are published and made available to the public – many times as a free service, sometimes for a fee. There are hundreds of well-known public blacklists.

Block: A refusal by an ISP or mail server not to accept an email message for delivery. Many ISPs block email from IP addresses or domains that have been reported to send spam or viruses or have content that violates email policy or spam filters.

Bulk Mail: Refers to mail that is automatically filtered to the bulk folder of a webmail or desktop email client. Also referred to as "Junk" or "Spam" folders in some email clients.

CAN-SPAM Act: Popular name for the U.S. law regulating commercial email (Full name: Controlling the Assault of Non-Solicited Pornography and Marketing Act of 2003).

Click-Through Rate: The ratio of unique click-throughs on a link or links within an email to the total number of recipients of the email, typically expressed as a percentage. The click-through rate does not take into account people who later came to a website in response to an email marketing campaign, so it can be used to measure the direct response only.

Click-to-Open Rate: The ratio of unique click-throughs on a link or links within an email to the total number of unique opens of the email, typically expressed as a percentage.

Cloudmark: A spam filter company that uses a network of users as a feedback mechanism to identify and block spam. Their Global Threat Network is fed by various means but most notably through their desktop spam filter and through 'This is Spam" buttons that ISP's contribute through their Cloudmark Authority product.

Complaint Rate: The ratio of unique complaints from an email campaign to the total number of delivered emails, typically expressed as a percentage. Recipients of an email can complain using the "This is Junk/Spam" button in their email software platform.

Content Filters: Software filters that block email based on text, words, phrases, or header information within the email itself. The goal is to identify spam and filter to the Bulk or Junk mail folders, although this often results in "false positives".

Deliverability: Refers to the whole subject area of getting your emails delivered to the right place.

Delivered: Refers to the number of emails that were successful in reaching the subscribers’ inboxes or junk folders. Typically thought of as the Total Number of Emails Sent minus Bounced Emails.

DKIM: DomainKeys Identified Mail (DKIM) lets an organization take responsibility for a message while it is in transit. The organization is a handler of the message, either as its originator or as an intermediary. Their reputation is the basis for evaluating whether to trust the message for delivery. Technically, DKIM provides a method for validating a domain name identity that is associated with a message through cryptographic authentication.

Domain: A particular organization's registered name on the Internet. For example,

Domain Name System (DNS): How computer networks locate Internet domain names and translate them into IP addresses. The domain name is the actual name for an IP address or range of IP addresses.

Domain Keys: Domain Keys in an email authentication system designed to verify the DNS domain of an email sender and the message integrity.

Email Change of Address (ECOA): A service that tracks email address changes and updates.

Email Client: A program used to read and send email messages. As opposed to the email server, which transports mail, an email client is what the user interacts with. Email clients can be software application like Outlook Express and Lotus Notes or webmail services like the ones provided by Yahoo, Hotmail and Gmail. Also referred to in Internet Email protocols as an MUA or Mail User Agent.

Email Service Provider (ESP): Another name for an email broadcast service provider, a company that sends bulk (volume) email on behalf of their clients.

Feedback Loop: A mechanism, proces,s and signal that are looped back to control a system within itself. A feedback loop is sometimes offered by ISPs to companies that wish to remove users that complain about email they receive via the "This is Junk/Spam" button.

From Line: Indicates who the sender of an email is. Typically comprised of a Friendly From Address and a Friendly From Name, which is usually the sender's or company's name.

Greylisting: A technique used by some ISPs and email receivers to thwart spammers. A receiving mail server using greylisting will temporarily reject any email from a sender it does not recognize. The receiver presumes that if the sender is legitimate, the originating server will most likely try again to send it later at which time the receiver will accept it. Greylisting presumes that if the sender is a spammer, they will not retry later to transmit their message. Greylisting has disadvantages and is somewhat controversial.

Hard Bounce: Message sent to an invalid, closed, or nonexistent email account. Typically, hard bounced emails can be identified with a 500 series SMTP reply code.

HTML Message: Email message which contains Hyper Text Markup Language syntax and encoding. HTML Messages must be properly encoded and receiving email clients (MUAs) must be capable of rendering HTML. Senders often utilize HTML in email messages to take advantage of text formatting, images, and design layout beyond what is possible with plain text messages and encoding.

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




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