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eMail Glossary

While you don’t need to be a computer engineer to deploy an email message. Learning the various acronyms and terminology, can help fool even the most experienced computer geek in thinking you know what you’re talking about.

“Any fool can know. The point is to understand.” ― Albert Einstein

A/B Split: Refers to a test situation in which two randomized groups of users are sent different content to test performance of specific campaign elements. The A/B split method can only be used to test one variable at a time.

Abandonment: As in call or site abandonment, when people leave a site, telephone call, etc. The abandonment rate measures the efficiency of the marketing tool. The abandonment rate is the number of users who abandon divided by the total number of unique visitors for a given period.

Above the Fold: The part of an email message or web page that is visible without scrolling. Material in this area is considered more valuable because the reader sees it first. It refers to a printing term for the top half of a newspaper above the fold. Unlike a newspaper, email and web page 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.

Acquisition Cost: In email marketing, the cost to generate one lead, newsletter subscriber or customer in an individual email campaign; typically, the total campaign expense divided by the number of leads, subscribers or customers it produced.

Acquisition List: A rented list of prospects to which email can be sent. Prospects on a legitimate acquisition list are supposed to have opted in to the list and possess a certain set of characteristics.

Accreditation-based systems: Third-party whitelist programs that certify senders to convince ISPs that those using the systems are legitimate mailers who should not be blocked. Examples include: Bonded Sender from ReturnPath and Safelist from Habeas.

Authentication: Technical standards through which ISPs and other mail gateway administrators can establish the true identity of an email sender. Examples of proposed authentication standards include: SPF (PO Box, AOL), Sender-ID (Microsoft), DomainKeys (Yahoo), and DKIM (Cisco and Yahoo).

Auto responder: Automated email message-sending capability, such as a welcome message sent to all new subscribers the minute they join a list. They can be triggered by users joining, unsubscribing or by email arriving at a particular mailbox. Auto responders may be used for more than a single message and can be a series of date or event-triggered emails.

Affiliate: A marketing partner that promotes your products or services under a payment for results agreement. The affiliate relationship ranges from simply carrying a button on a web page to full-blown email campaigns by the affiliate.

API: Application Program Interface , how a program (application) accesses another to transmit data. A client may have an API connection to load database information to an email vendor automatically and receive data back from the email.

Alt Text: The alt text is used to specify text for an image on a web page in the event that images are turned off on a visitor's web browser.

Bayesian Filter: An anti-spam program that evaluates header and content of incoming email messages to determine the probability that it is spam. Bayesian filters assign point values to items that appear frequently in spam, such as the words money-back guarantee or free. A message that accumulated too many points is either rejected as probable spam or delivered to a junk mail folder. Also Content-Based Filter.

Blacklist, public: A list of IP addresses believed to send spam. Public blacklists are created and maintained by third parties; sometimes used by ISPs as another filtering mechanism to block email delivery. Blacklist, private: A list of IP addresses believed to send spam, compiled by an ISP based on user complaints, mail sent to spam trap addresses, and “unknown user” rates. Each receiving ISP uses its own private blacklists to block email delivery.

Bounce: A message sent by a receiving system that “bounces back” to the originating server to alert the sender of the non-delivery.

Block : A block bounce is recorded when the error code includes any language that refers to a blacklist or delivery issue. Blocked bounces can be generated from the sending IP, domain name, or message content.

  • Hard : A hard bounce occurs when the recipient’s mail server replies with 5xx error, which in most cases means that the attempt to deliver to that recipient will never succeed. An example of a hard bounce error is recipient@domain.com does not exist, which commonly occurs when a list of members has not been contacted recently.
  • Soft : A soft bounce occurs when the recipient’s mail server replies with an error other than 5xx, or never replies at all. An example of a soft bounce error could be caused by a server that overloaded or a user whose mailbox is full.

Bulk mail folder: Folder within email clients to which questionable email is often directed. Also referred to as “Junk” or “Spam” folders in some email clients.

Blackhole: Term describing what happens to email that is blocked without a bounce response to the sender.

Blast: In postal mail or email, and also referred to as solo blasts, a reference to promotional campaigns done on a one-time basis. Distinct from ongoing communications, such as email newsletters.

Broadcast: The process of sending the same email message to multiple recipients. B2B: Business-to-business: Also B-2-B and B-to-B.

CallerID: The original name of the authentication standard developed by Microsoft that later became SenderID

CTA: Call to Action, in a marketing message, web ad, email, etc., the link or body copy that tells the recipient what action to take.

CAN-SPAM: Passed in December 2003, the Federal legislation governing unsolicited commercial email that went into effect on January 1, 2004. This law does not prohibit unsolicited commercial email, but it does regulate how it must be sent. Lawmakers intended to protect the end user and to make prosecution of spammers easier.

Catch-All: An email server function that forwards all questionable email to a single mailbox. The catch-all should be monitored regularly to find misdirected questions, unsubscribes or other genuine live email.

CBL : Composite Blocking List, the CBL takes its source data from very large spamtraps/mail infrastructures, and only lists IPs exhibiting characteristics which are specific to open proxies of various sorts (HTTP, socks, AnalogX, wingate etc) and dedicated Spam BOTs (such as Cutwail, Rustock, Lethic etc) which have been abused to send spam, worms/viruses that do their own direct mail transmission, or some types of trojan-horse or “stealth” spamware, dictionary mail harvesters etc.

Challenge Response: Method of approving senders to specific email addresses that asks the email sender to answer a question proving he is a real person and not a “spam cannon” attempting to send email. Primarily used by Earthlink and selected client-side filters.

Commercial email: Marketing or sales oriented email that is sent in bulk.

Confirmed opt-in (COI): A new subscriber asks to be subscribed to the mailing list, but unlike unconfirmed opt-in, a confirmation e-mail is sent to verify it was really them. Many believe the person must not be added to the mailing list unless an explicit step is taken, such as clicking a special web link or sending back a reply e-mail. This ensures that no person can subscribe someone else out of malice or error. Mail system administrators and non-spam mailing list operators refer to this as confirmed subscription or closed-loop opt-in.

Content filters: Software filters that block email based on 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”.

Commercial Email: Email whose purpose, as a whole or in part, is to sell or advertise a product or service, or to persuade users to perform an act, such as to purchase a product or click to a website whose contents are designed to sell, advertise or promote.

Conditional Content: Use of a database to allow or block content based on user behavior. This is done with if and then statements. Content-Based Filters: A type of filtration that sorts messages based on strings or key words located within the message. Filtering can take place based upon a score assigned to some words or phrases, or based on binary if/then statements. Example: Block if free in subject field.

Conversion: When a recipient of a marketing message performs a desired action based on a mailing you have sent. A conversion could be a monetary transaction, such as a purchase made after clicking a link. It could also include a voluntary act such as registering at a website, downloading a white paper, signing up for a web seminar or opting in to an email newsletter.

Conversion Rate: The percentage of visitors/users who convert on the action of a web page or campaign. For example, actions may be purchasing, submitting a form, downloading content, calling a telephone number or making an extended site visit.

Cost per Lead: Where the advertiser pays a set amount for each lead generated by a marketing campaign. Also CPL.

CPM: (Cost per Thousand): An ad-buying model more common in web publishing than search where the advertiser pays for a set number of page impressions, paying by the thousand.

CPA :(Cost Per Action or Cost Per Acquisition): A method of paying for advertising in which payment is based on the number of times users complete a given action, such as purchasing a product or signing up for a newsletter that takes place as a result of the marketing effort.

CPC: (Cost Per Click): A method of paying for advertising. Different from CPA because all you pay for is the click, regardless of what that click does when it gets to your site or landing page.

Creative: An email messages copy and any graphics.

CRM: (Customer Relationship Management): The software and processes of tracking the information that defines a prospect or customer relationship. CRM systems typically store contact and interaction data, such as number and dates of touches, products considered.

Cross-Campaign Profiling: A method used to understand how email respondents behave over multiple campaigns.

Click-through Rate: The % of users that click on a message. This can be calculated using number of recipients that were scheduled, received the message, or opened the message. CTA: Call to Action, in a marketing message, web ad, email, etc., the link or body copy that tells the recipient what action to take.

Click-to-Open Ratio: An email metric that looks at the quality of content by comparing the number of people who opened the email with those that clicked. Several factors can have a dramatic impact on CTO ratio, including filtering of images that suppresses open rate and newsletters that include only snippets of content in an email, elevating click numbers.

CLV: (Customer Lifetime Value): A measure of the total amount the customer is going to spend with a merchant during their tenure. Usually calculated by their spending per year multiplied by the average number of years they are likely to be a customer.

Challenge-Response System: An anti-spam program that requires a human being on the sender's end to respond to an emailed challenge message before their messages can be delivered to recipients. Senders who answer the challenge successfully are added to an authorization list. Bulk mailers can work with challenge-response if they designate an employee to watch the sending address's mailbox and to reply to each challenge by hand.

Churn: How many subscribers leave a mailing list (or how many email addresses go bad) over a certain length of time, usually expressed as a percentage of the whole list.

DBL : Domain Block List, DBL is a realtime database of domains (typically web site domains) found in spam messages. Mail server software capable of scanning email message body contents for URIs can use the DBL to identify, classify or reject spam containing DBL-listed domains.

DNSBL : (DNS-based Blackhole List, Block List, or Blacklist; see below) is a list of IP addresses published through the Internet Domain Name Service (DNS) either as a zone file that can be used by DNS server software, or as a live DNS zone that can be queried in real-time. DNSBLs are most often used to publish the addresses of computers or networks linked to spamming; most mail server software can be configured to reject or flag messages which have been sent from a site listed on one or more such lists.

Deliverability: This term describes the overall amount of messages that reached the inbox and can be attributed to a specific campaign or for a sender overall.

Delivery monitoring: A process, usually using third party tools and techniques, to measure true delivery rates by campaign and ISP. Also tracks the amount and type of email tagged and/or blocked by server and client-side filters.

Delivery Rate: The % of messages delivered (not bounced) versus the total number scheduled.

Dedupe: Identifying and consolidating duplicate names, usually done in a merge/purge operation.

Dedicated Server: An email server used by only one sender. A dedicated server often costs more to use because the expense't spread among multiple users, but it performs better than a shared server. Email usually goes out faster; the server is more secure; and it eliminates the possibility that another sender could get the server blacklisted for spamming.

Deferred Conversions: Sales that take place following a website session that may result from it. With many online marketing tactics, it's not always possible to discern whether a sale took place as the result of some past interaction. Also Latent Conversions.

Delivery Tracking: The process of measuring delivery rates by format, ISP or other factors and delivery failures (bounces, invalid address, server and other errors).

Deploy: To send a marketing campaign into the field.

Dictionary attack: A type of spam program that bombards a mail server with millions of alphabetically generated email addresses in the hope that some addresses will be guessed correctly.

Double-Optin: See Confirmed Optin and Deliverability

Domain: Internet addresses made up for words that correspond to the Internet Protocol (IP) numbers computers use to find each other. Domains always have two or more parts, separated by “dots”.

DomainKeys: Email authentication system proposed by Yahoo! that checks an encrypted “key”embedded in each email sent against a list of public records to positively confirm the identity of the sender. Not the same as DKIM

DKIM: DomainKeys Identified Mail is a method for associating a domain name to an email message, thereby allowing a person, role, or organization to claim some responsibility for the message. The association is set up by means of a digital signature which can be validated by recipients. Responsibility is claimed by a signer —independently of the message's actual authors or recipients— by adding a DKIM-Signature: field to the message's header. The verifier recovers the signer's public key using the DNS, and then verifies that the signature matches the actual message's content. DKIM, is the result of merging DomainKeys and Identified Internet Mail.

DNS: Domain Name System (DNS) translates domain names into an IP address to find the owner's site.

Dynamic Content: Email newsletter content that changes from one recipient to the next according to a set of predetermined rules or variables, usually according to preferences the user sets when opting in to messages from a sender. Dynamic content can reflect past purchases, current interests or where the recipient lives.

Email delivery rates: The percentage of email that gets delivered as intended; compiled from seedlist-based monitoring services and SMTP log files.

ECOA: Email Change of Address (ECOA) is a process that provides updated email addresses for data files based on consumer-provided, permission-based data.

Email append: Process that adds email addresses to postal files by merging files to match the postal address against email information in other files.

ESP: An Email Service Provider is a hosted service that manages a company’s customer database or list and provides tools for sending out different types of emails on a one-off or automated fashion. Most commonly used for “batch and blast” newsletters and email marketing, ESPs also provide services for managing transactional email messages, autoresponders, password reminders, alerts and more.

Email Client: The software recipients use to read email, such as Outlook Express or Lotus Notes.

Email Domain: The portion of the email address to the right of the @ sign. Useful as an email address hygiene tool, e.g., identify all records where the consumer entered name@aol– as their email address and correct it to name@aol.com.

Email Filter: A software tool that categorizes sorts or blocks incoming email, based either on the sender, the email header or message content. Filters may be applied at the recipient's level, at the email client, the ISP or in combination.

Email Friendly Name: The portion of the email address that is displayed in most, though not all, email readers in place of, or in addition to, the email address. Also Display Name or From Name.

Email Harvesting: An automated process in which a robot program searches web pages or other Internet destinations for email addresses. The program collects the address into a database, which frequently gets resold to spammers or unethical bulk mailers. Many U.S. state laws forbid harvesting. CAN-SPAM does not outlaw it by name but allows triple damages against violators who compiled their mailing lists with harvested names.

Email Newsletter: Content distributed to subscribers by email on a regular schedule. Content is seen as valued editorial in and of itself rather than primarily a commercial message with a sales offer. See Ezine.

Email Prefix: The portion of the email address to the left of the @ sign.

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

Enhanced Whitelist: A super whitelist maintained by AOL for bulk emailers who meet strict delivery standards, including fewer than one spam complaint for every 1,000 email messages. Emailers on the enhanced whitelist can bypass AOL 9.0's automatic suppression of images and links.

Event-Triggered Email: Pre-programmed messages sent automatically based on an event such as a date or anniversary.

Eyetracking: A type of web page testing that follows the eye movements of participants to gauge how they interact with the page.

False-negative: When spam filtering devices fail to detect spam and allow it to be delivered.

False-positive: When spam filtering devices inaccurately identify legitimate email as spam and block delivery.

Feedback loop (FBL), sometimes called a complaint feedback loop, is an inter-organizational form of feedback by which a MailboxProvider (MP) forwards the complaints originating from their users to the sender's organizations. MPs can receive users' complaints by placing report spam buttons on their webmail pages, or in their email client. This is only beneficial is a sender is signed up to a FBL reporting system. Since “Report Spam” can only be forwarded to a sender, if they are signed up to the program.

Filter: See Email Filter.

Footer: An area at the end of an email message or newsletter that contains information that doesn't change from one edition to the next, such as contact information, the company's postal address or the email address the recipient used to subscribe to mailings. Some software programs can be set to place this information automatically.

Forward (also Forward to a Friend): The process in which email recipients send an email to people they know, either because they think their friends will be interested in the message or because of incentives to forward messages. Also Viral Marketing.

Frequency: The number of times someone is exposed to an advertisement or marketing message.

From: Whatever appears in the email recipient's inbox as the visible From name. It is chosen by the sender and may be a personal name, a brand name, an email address, a blank space or alphanumeric gobbledygook. Note: This is not the actual From contained in the header (see below) and may be different than the email reply address. Also referred to as Email Friendly Name.

Greylisting: Process of routing email to a bulk folder if it is borderline spam, as determined by a receiving ISP.

Hard Bounce: see bounce

Harvesting: Process that crawls the Internet to gather email addresses from Web sites and then uses them to create lists for spamming.

Header: The first part of an email message that contains controlling and meta-data such as the subject, origin and destination email addresses, the path an email takes, and its priority. May be used to filter, track spammers or uncover information about delivery rates.

Honeypotting: Occurs when planted email addresses find their way into permission email marketer's lists. ISPs and spam-fighters place these addresses on the web waiting for them to be harvested by a spammer or unreputable list creator. If an emailer sends to a list containing a honeypot, all mail going to the ISP using the honeypot is blocked, even if some or most list recipients did opt in.

House List: List of email addresses an organization develops on its own.

HTML: The most common of the programming languages used to create web pages.

HTML Message: Email message that contains any type of formatting other than text. This may be as simple as programming that sets the text in a specific font (bold, italics, Courier 10 point, etc.). It also includes any graphic images, logos and colors.

HTML Sniffer: Technology embedded in email software that determines if users email clients can receive HTML content.

Hygiene: The process of cleaning a database to correct incorrect or outdated values.

IP addresses: Internet Protocol addresses. The numeric identification number that refers to a specific machine on the Internet.

Internet Service Provider (ISP): Company that provides access to the Internet through connectivity services. Examples include AOL, Gmail, Yahoo, and Verizon

IMAP: (Internet Message Access Protocol), A standard protocol for accessing email from a server.

Incentive: The use of motivational devices such as competitions, games, premiums, special pricing, to promote the sale of a merchandise or service.

Impression: A single view of one page by a single user, used in calculating advertising rates.

Inactivity: When a list member or registered user has been inactive for some period of time. There are no industry standards, as inactivity depends on the nature of the relationship and frequency of communication. For example, a list member who is mailed quarterly wouldn't be considered inactive as quickly as one who is mailed weekly.

Landing Page: The destination web page for people who respond to an advertisement designed specifically for that campaign and audience. The campaign might be in any medium, but is typically email, search or online ad driven. The key difference between a home page and landing page is that the former must be all things to all visitors, while the landing page should be very narrowly designed for the campaign and, perhaps, for a segment of the audience responding to it.

Latency: In regards to marketing and conversion, the likelihood of a conversion to take place after an initial contact or site visit.

Lead Development: The process of moving a qualified lead toward becoming a prospect (someone in the sales funnel).

List hygiene: Process of cleaning email files to ensure all addresses are accurate, current, opt-in and deliverable.

List: The list of email addresses to which you send your message. Can be either your house list or a third-party list that sends your message on your behalf.

List-Unsubscribe: is an optional email header line that specifies means to unsubscribe from a mailing list or newsletter. A message can contain multiple means to unsubscribe: an email address, for example, and a web page. If you do not find unsubscription instructions in a message from a mailing list, you can examine the full message source for lines starting with “List-Unsubscribe” and take appropriate action.

List Fatigue: A condition producing diminishing returns from a mailing list whose members are sent too many offers, or too many of the same offers, in too short a period of time.

List Management: How a mailing list is set up, administered and maintained. The list manager has daily responsibility over list operations, including processing subscribes and unsubscribes, bounce management, list hygiene, etc. The list manager can be the same as the database manager but is not always the same person as the list owner.

List Owner: The organization or individual who has gathered a list of email addresses. Ownership does not necessarily imply with permission.

List Rental: The process in which a publisher or advertiser pays a list owner to send its messages to that list. Usually involves the list owner sending the messages on the advertiser's behalf. (If someone hands over their list to you, beware).

List Sale: The actual purchase of a mailing list along with the rights to mail it directly. Permission can only be sold if the subsequent mailings continue to match the frequency, brand name, content and from of the past owner's mailings and even then this is a somewhat shaky procedure on the spam front. You are in effect buying a publication and not just a list.

Machine-learning filters: Filters run by machines that determine whether to block email based on algorithms that point to whether the message is likely spam.

Mail Bomb: An orchestrated attempt to shut down a mail server by sending more messages than it can handle in a short period of time.

Mail Loop: A communication error between two email servers, usually happening when a badly configured email triggers an automated response from the recipient server.

Mailing List: A list of email addresses that receive mailings or discussion group messages.

Mailto: A code to make an email address in either a text or HTML email immediately clickable (mailto:JohnDoe@anywhere.com). When the link is clicked, it usually opens the user's email client and inserts the email address in the To: link of a blank message.

Multichannel: A differentiator of merchants that employ multiple sales channels, as opposed to being strictly one (brick and mortar) or the other (web only or pureplay).

Mosaic: is simply a pixilated version of your email using html tables. Therefore, you can create a visual representation of your email without using images

Multichannel Marketing: Marketing efforts that use multiple media to target unique prospects. For example, sending direct postal mail and email with complimentary messaging and offers to the same people with coordinated timing.

MIME: Multipurpose Internet Mail Extensions, a standard for sending non text information. Commonly an email message is encoded in a MIME format allowing HTML compatible MUAs to display the HTML portion only.

MTA: Mail Transfer Agent. This is a mail server used to send and receive mail. Examples of MTA’s include the Port 25, StrongMail MTA, and Sendmail.

MUA: Mail User Agent. This interprets and displays email messages. Examples include Outlook, Eudora, and Mozilla Thunderbird.

Multivariate Testing: Using a statistical model to allow the simultaneous testing of multiple variables. Contrast with A/B testing, which examines only one variable at a time. Also known as the Taguchi Method.

Nth Name: The act of segmenting a list for a test in which names are pulled from the main list for the test cell by number, such as every 5th name on the list. See also A/B Split.

NJABL : Not Just Another Bogus List, or NJABL, is a DNS blacklist, maintains a list of known and potential spam sources (open mail relays, open proxies, open form to mail HTTP gateways, dynamic IP pools, and direct spammers) for the purpose of being able to tag or refuse e-mail and thereby block spam from certain sources. NJABL automatically retests only listed open relays every 90 days

Open Rate: The percentage (%) of users that open an HTML message versus the number of messages scheduled or delivered depending on the criteria. An open is captured when a user downloads a small, normally invisible image

Open relay: SMTP email server that allows the third-party relay of email messages through the SMTP “port” on a server (port 25). While this feature of SMTP servers has legitimate uses, spammers have learned how to locate unprotected servers and use them to send spam.

Open proxy: Software that exists on a server that allows the third-party relay of e-mail messages through ports other than port 25.

Opt-in: Process of agreeing to receive email from a business source. Confirmed opt-in refers to a double-check procedure in which a decision to be included on a mailing list is confirmed.

Opt-out: Process of declining to receive email from a business source or unsubscribing if the recipient is already on a mailing list.

Pass-Along: An email recipient who received a marketing message that was forwarded from a subscriber. Some emails offer forward to a friends– in the creative, but the vast majority of pass-alongs happen using email clients. Pass-alongs can affect the formatting of the email, often stripping off HTML. Also Viral.

Passed Parameters: The act of including known subscriber information in a redirect URL. This allows you to provide web applications that can pre-populate form values requiring the subscriber to do less typing.

PBL: Policy Block List, PBL is a DNSBL database of end-user IP address ranges which should not be delivering unauthenticated SMTP email to any Internet mail server except those provided for specifically by an ISP for that customer's use.

Phishing: (Pronounced 'fishing') The act of forging emails that claim to be from a legitimate sender, such as a bank, for the purpose of identity theft or robbery. Phishing emails usually link to a replica of a legitimate web page that tries to trick users into submitting personal or financial information or passwords.

Plain Text: Text in an email message that includes no formatting code. See HTML. POP (Post Office Protocol): Used by email clients to send to or receive messages from an email server. Not to be confused with Point of Presence, an access point for the Internet

Postmaster: The person who manages mail servers at an organization. Usually the one to contact at a particular server/site to get help, information, or to log complaints.

Preferences: Options a user can set to determine how they want to receive your messages, how they want to be addressed, to which email address messages should go and which messages they want to receive from you.

Preview Pane: The window in an email client that allows the user to scan message content without actually clicking on the message. See Open Rate.

Privacy Policy: A clear description of how your company uses the email addresses and other information it gathers via opt-in requests for newsletters, company information or third-party offers or other functions. If you rent, sell or exchange your list to anyone outside your company, or if you add email addresses to opt-out messages, you should state so in the privacy policy. State laws may also compel you to explain your privacy policy, where to put the policy statement so people will see it, and even in the form the policy should be displayed.

Promotional Messages– Are emails that are sent with the soul purpose of marketing ones goods and services.

Qualified Lead: While the definition varies from marketer to marketer, a qualified lead is generally the next step up from inquiry the lead fits some criteria to warrant lead development. It may be as simple as anyone who searched for this term is qualified– to they only corresponded to three of five criteria from our registration form, they're not qualified.

Queue: Where an email message goes after you send it but before the list owner approves it or before the list server gets around to sending it. Some list software allows you to queue a message and then set a time to send it automatically, either during a quiet period on the server or at a time when human approval isn't available

Ranking: A web page's position in search engine results for a particular keyword/search phrase. Higher rankings typically indicate better SEO, more traffic and higher quality traffic.

Read Email: There is no real measure of read email, although the term is sometimes used as a synonym for opened email. Only opens and clicks are measurable. You can never know if a recipient read your message.

Readability: The degree to which an email client correctly renders an HTML email.

Rich media: A category of web technologies that utilize streaming video, audio and other static or animated files to create an advanced media experience for viewing content.

ROKSO : The Register of Known Spam Operations, database collates information and evidence on known professional spam operations that have been terminated by a minimum of 3 Internet Service Providers for spam offenses.

Referrer: The address of the web page from which a visitor arrived. Also Referring URL.

Registration: The process where someone not only opts in to your email program, website membership program, etc., but provides some additional information, such as name, address, demographic data or other relevant information, usually by using a web form.

Reply-To: The email address that receives messages sent from users who click reply in their email clients. Can differ from the From address, which can be an automated or unmonitored email address used only to send messages to a distribution list. Reply-to's should always be a monitored address.

Reverse DNS: The process in which an IP address is matched correctly to a domain name, instead of a domain name being matched to an IP address. Reverse DNS is a popular method for catching spammers who use invalid IP addresses. If a spam filter or program can't match the IP address to the domain name, it can reject the email.

ROI: (Return on Investment), either mathematical or anecdotal analysis of payback for a project.

SBL: Spam Block List, is an email address traditionally used to expose illegitimate senders who add email addresses to their lists without permission. But they are also set up to identify email marketers with poor permission and list management practices.

Seed list: A list of email addresses that should be included in every email event to monitor delivery across email platforms. Can be executed in-house or through a third-party vendor.

Sender-ID: An authentication standard proposed by Microsoft, that compares an email sender's “From” address to the IP address authorized to send email from that domain.

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

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

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.

SPF: (Sender Policy Framework) compares an email sender's actual IP address to a list of IP addresses authorized to send mail from that domain. This list is published in the domain's DNS record.

SMTP: log file: A file showing all conversations back and forth between servers during the email send and receive process. Used to uncover problems with various deliverability factors such as unknown user rates.

Social Sharing: Tools and tactics that enable email recipients to share email content on popular social networks and other social media sites.

Spam: Widely-used slang reference to unsolicited commercial email messages. Named after the Monty Python “Spam” song.

Spam filter: Systems that watch for spam and block it before it can hit the inbox. Spam filters can be complaint or content based.

Spam-trap: address: An email address that is set up specifically to catch people who are harvesting addresses or using directory attacks to send unsolicited email. Used by Brightmail, ISPs and many in the anti-spam community.

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 because of spam complaints.

Spamdexing: Any technique designed to fool search engine spiders, and increase or artificially change a search ranking or result.

Soft Bounce: See Bounce

Suppression list: A list of email addresses kept by a single organization that should not be mailed to any longer. Usually owners of the addresses on the list have specifically requested inclusion. Required by CAN-SPAM.

SURBL: SURBLs (no longer an acronym) are lists of Uniform Resource Identifier (URI) hosts, typically web site domains, that appear in unsolicited messages. SURBLs can be used to search incoming e-mail message bodies for similar sites to help evaluate whether the messages are unsolicited. For example, if http://www.buythisstuff.com is blacklisted, then e-mail messages with a message body containing this URI may be classified as unsolicited. SURBLs differ from prior DNSBLs, which commonly list mail sending IP addresses. SURBLs are a specific instance of the general URIBL list type. URIBL.com is a different, unrelated URIBL-type list.

Subject Line: Copy that identifies what an email message is about, often designed to entice the recipient into opening the message. The subject line appears first in the recipient's inbox, often next to the sender's name or email address. It is repeated in the email message's header information inside the message.

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. (If you accept verbal subscriptions, you should safeguard yourself by recording it and storing recordings along with time and date, in a retrievable format).

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.

Third Party Messages – These are messages, in which email recipients “granted permission” to the original advertiser (opt-in) to rent or sell the recipients email address and information. These messages are normally sent through “email publishers” who then send email advertisements .

Transactional Messages: Messages that are related to a service the user opted-in to and whose primary purpose is not to advertise a product or the use of a service. Typical examples of transactional messages include an order confirmation after you make a purchase or a bank statement.

TLD : A top-level domain is one of the domains at the highest level in the hierarchical Domain Name System of the Internet. The top-level domain names are installed in the root zone of the name space. For all domains in lower levels, it is the last part of the domain name, that is, the last label of a fully qualified domain name. For example, in the domain name www.example.com, the top-level domain is .com (or .COM, as domain names are not case-sensitive). Management of most top-level domains is delegated to responsible organizations by the Internet Corporation for Assigned Names and Numbers (ICANN), which operates the Internet Assigned Numbers Authority (IANA) and is in charge of maintaining the DNS root zone.

Test: A necessary step before sending an email campaign or newsletter. Many email Clients permit you to send a test email before sending a regular email newsletter or solo mailing, in which you would send one copy of the message to an in-house email address and then review it for formatting or copy errors or improperly formatted links. Email marketers should also send a test campaign to a list of email addresses not in the deployment database to determine likely response rates and how well different elements in the message perform.

Text Newsletter: Plain newsletter with words only no colors, graphics, fonts or pictures. Can be received by anyone who has email.

Thank-You Page: Web page that appears after user has submitted an order or a form online.

Throttling: The practice of regulating how many email messages 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.

Unconfirmed opt-in: A new subscriber first gives his or her address to the list software (for instance, on a Web page), but no steps are taken to make sure that this address actually belongs to the person. This can cause e-mail from the mailing list to be considered spam because simple typos of the email address can cause the email to be sent to someone else. Malicious subscriptions are also possible, as are subscriptions that are due to spammers forging email addresses that are sent to the e-mail address used to subscribe to the mailing list.

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

URIBL: URL based blacklist, a URI DNSBL is a DNSBL that lists the domain names and IP addresses which are found in the “clickable” links contained in the body of spams, but generally not found inside legitimate messages.

UCE :(Unsolicited Commercial Email), Also called spam or junk mail.

Unique Reference Number: A unique number assigned to a list member, usually by the email broadcast software, and used to track member behavior (clicks, subscribes, unsubscribes) or to identify the member to track email delivery.

Unsubscribe: A user seeking to cancel their subscription to an electronic mailing list or online service.

Verified opt-in: Formerly known as double opt-in. Requires secondary confirmation from an email address to confirm intended registration to receive email. back to top

Vendor: Any company that provides a service. See Email Vendor

Verification: A program that determines an email came from the sender listed in the return path or Internet headers; designed to stop email from forged senders.

Video Email: An email message that includes a video file, either inserted into the message body, accessible through a hotlink to a website or accompanying it in an attachment . This is the least desirable because many ISPs block executable attachments to avoid viruses.

Web Bug: A 1-pixel by 1-pixel image tag added to an HTML message and used to track open rates by email addresses. Opening the message, either in the preview pane, or by clicking on it, activates the bug and sends a signal to the website, where special software tracks and records the signal as an open. Also Web Beacon.

Webmail: Any of several web-based email clients where clients have to go to a website to access or download email instead of using a desktop application. Some examples are Gmail, Yahoo and Hotmail.

Welcome Message: Message sent automatically to new list members as soon as their email addresses are added successfully.

Whitelist: A list of trusted IP addresses and domains that allows all mail from these addresses to be delivered.

XBL: Exploits Block List , is a realtime database of IP addresses of hijacked PCs infected by illegal 3rd party exploits, including open proxies (HTTP, socks, AnalogX, wingate, etc), worms/viruses with built-in spam engines, and other types of trojan-horse exploits