EchoFetch Website Glossary

A Glossary of All Things Pertaining to Email

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A – D

ADA

Americans with Disabilities Act

The ADA is a federal civil rights law that prohibits discrimination against people with disabilities in everyday activities, such as visual, auditory, physical, speech, cognitive, language, learning, and neurological disabilities.

See ADA.gov for more information.

API

Application Programming Interface

An API is an application programming interface for two or more computer programs or components to communicate with each other. It is a type of software interface that offers a service to other pieces of software using requests and responses.

Alt-Text

Alternative Text

Alt-text is the text or copy encoded or embedded in a digital image and displays when hovering a mouse cursor over that image. Alt-text is also readable by assistive technologies.

Blacklist

A list of known spam sources.

A blacklist is a list of IP addresses that have been reported and listed as “known” sources of spam. Public blacklists are published and made available to the general public, which users across the globe can contribute to and use, either for free or as a paid service.

Block

A refusal to deliver an email from the sender.

A block is a mailbox provider or server's refusal to accept an email message for delivery. Many mailbox providers block emails using their IP address or domain using a public or private blacklist where they were reported to send spam or viruses. They can also be blocked for content that violates their email policy or spam filters.

Bounce

A failed delivery error message.

A bounce is an error message mailbox providers send back to the sending email server when an email send attempt fails delivery. This can be a permanent (Hard Bounce) or temporary (Soft Bounce) error. 

CAN-Spam Act

Controlling the Assault of Non-Solicited Pornography and Marketing Act.

The CAN-Spam Act is a United States law establishing national standards for the sending of commercial e-mail and some text messages sent to wireless devices, including content on commercial websites.

See details at the Federal Trade Commission's website.

CASL

Canada’s Anti-Spam Legislation.

CASL reinforces best practices in email marketing and combat spam and related cyber threats. These threats include identity theft, phishing and the spread of malicious software, such as viruses, worms and trojans (malware).

See details at the Government of Canada's website.

CNAME

Canonical Name

CNAME records are DNS records that map an alias name or subdomain (www or blog) to a root domain name (echofetch.com). These records are often used to point services hosted on different IP addresses to a primary domain name.

CSS

Cascading Style Sheets

CSS is a style sheet language used for specifying or enhancing the presentation and styling of a document written in a markup language, such as HTML. It provides more control of the document’s presentation and styling, better website speed, and is easier to maintain than HTML alone.

DKIM

DomainKeys Identified Mail

DKIM is a protocol that authenticates every email with a cryptographic signature. DKIM signatures allow mailbox providers to associate an email with its sender and verify that the content of the email has not been changed during transmission.

DMARC

Domain-based Message Authentication, Reporting, and Conformance.

DMARC is an email authentication protocol that protects domain owners from unauthorized use. It tells a receiving email server what to do if neither SPF nor DKIM passes and provides a reporting mechanism for authentication failures.

DNS

Domain Name System

DNS provides translation services between human-readable domain names and machine-readable IP addresses. The most common analogy for DNS is that it serves as the phone book for the Internet.

Domain Name

Identification label for a website.

A domain name is an identification label to indicate ownership or control of internet resources, such as websites (echofetch.com), computers, networks, and services.

E – K

Email

Electronic Mail

Email, or e-mail, is a communication method of transmitting and receiving digital messages across computer networks such as a computer or smartphone.

Email Accessibility

An email that is created for everyone’s user experience.

Email accessibility is the practice of writing, designing, and coding HTML emails that people can easily understand and engage with, regardless of visual, physical, cognitive, or neurological disabilities.

See our guide to make your emails more accessible.

Email Authentication

SPF, DKIM, and DMARC

Email authentication is the process of verifying the digital identity of the sender of a communication. In email marketing, the most widely used and accepted forms of email authentication are SPF, DKIM, and DMARC.

Email Client

Software or webmail

An email client is a program a user interacts with to read and send email messages. Email clients can be software applications on your desktop or smartphone, like Outlook Express, Thunderbird, and Lotus Notes, or webmail services like Yahoo, Hotmail, and Gmail.

ESP

Email Service Provider

An ESP is a company that sends emails on behalf of its clients. It may also provide other email-related services like list management, deliverability monitoring, and performance reporting, such as Mailchimp, Mailgun, Constant Contact, etc.

FBL

Feedback Loop

Feedback loops allow senders to receive alerts from mailbox providers when a subscriber complains. The mailbox provider forwards the complaints from their users to the sender's organization, primarily so the sender can suppress this user in their database. Senders can see their compliance status with some mailbox providers, such as Google Postmaster Tools, or Yahoo Sender Hub, etc.

GDPR

General Data Protection Regulation

The GDPR is a European law that protects the privacy and security of personal data and applies to the collection and use of personal information by organizations in the European Economic Area (EEA) and certain non-EEA organizations that process EEA data. It is toughest privacy and security law in the world.

See details on the Information Commissioner's Office website.

Hard Bounce

A permanent failed delivery error message.

A hard bounce is an error classification sent from a mailbox provider to the sender when an email sender attempts to send an email, and it fails delivery. The bounce can be from an invalid or unknown email address or the recipient has blocked the sender. This is a permanent error; this email address should be removed immediately.

HTML

Hypertext Markup Language

HTML is the standard markup language for documents designed to be displayed in a web browser or email. Most emails are either text-only or HTML to include graphics, layout, decorative links, and color.

IMAP

Internet Message Access Protocol

IMAP is a protocol allowing an email client to access email on a remote mail server. This allows users to access their email from any device, such as a phone, laptop, or tablet, without downloading it.

Inactive Subscribers

Subscribers who haven’t interacted with your emails.

Inactive subscribers, or “non-responders,” are email recipients who have not taken action on your emails (opens, clicks) within a certain amount of time.

Infrastructure

Physical Servers

Infrastructure refers to the hardware used to deploy emails or have an email service provider deploy them on your behalf. The hardware is commonly referred to as your mailing transport agent (MTA).

IP Address

Internet Protocol Address

An IP address is a unique number assigned to each device connected to the internet and can be dedicated or shared.

A dedicated IP address allows the sender complete control of emails sent from their IP address and the resulting reputation.

A shared IP address means other senders are mailing campaigns utilizing the same IP address.

ISP

Internet Service Provider

An ISP is a company that provides individuals and organizations access to the internet and other related services.

L – O

List Hygiene

Subscriber list maintenance

An ISP is a company that provides individuals and organizations access to the Internet and other related services.

List-Unsubscribe

A mechanism allowing users to remove themselves from an email list.

The list-unsubscribe header is an email header that provides instructions for a brand's unsubscribe process. Mailbox providers can then display an unsubscribe button for recipients to click on if they would like to stop future messages automatically.

MIME

Multipurpose Internet Mail Extensions

MIME is an internet standard that allows the exchange of various data files via email, including audio, video, images, and application programs.

MTA

Message Transfer Agent

MTA is email server software that receives and relays emails from one computer to another using the Simple Mail Transfer Protocol (SMTP).

MUA

Mail User Agent

MUA is email client interface software that allows users to access, create, format, and send email messages.

P – S

POP3

Post Office Protocol 3

POP3 is an application-layer Internet standard protocol used by e-mail clients to retrieve e-mail from a mail server. Along with IMAP, it is one of the most common protocols for email retrieval.

Pristine Spam Trap

An email address created solely to catch spammers.

Pristine spam traps, or “honeypots,” are email addresses created exclusively to capture spammers. An actual human never owns these email addresses, does not subscribe to email programs, and does not make purchases. Many spam trap operators will post (seed) pristine traps across the internet on various participating websites. They are usually hidden in the webpages' background code and acquired by spambots when scraping email addresses.

Recycled Spam Trap

An old email address that was reused or recycled to catch spammers.

Recycled spam traps are email addresses that a real person once used. These email addresses are abandoned accounts that mailbox providers recycle as spam traps. Before turning an abandoned email address into a spam trap, mailbox providers will return unknown user error codes for a year. Once a mailbox provider reactivates (recycles) the abandoned email address, mail is again allowed to be received by the email address. If you’re hitting recycled spam traps, this typically indicates a problem with your data hygiene.

Sender Reputation

The reputation score of your email domain and IP address.

Sender reputation, or email reputation, determines the validity of an incoming sender by analyzing past sending behaviors. Mailbox providers evaluate this metric when deciding whether to deliver an incoming email to the inbox or the spam folder.

SEO

Search Engine Optimization

SEO is the process of getting traffic from free, organic, editorial, or natural search results in search engines.

Spam

Unwanted, unsolicited messages sent in bulk by email.

Spam is an email message you did not ask for and do not want from somebody you do not know who wants to sell you something, such as a product or a service.

SPF

Sender Policy Framework

SPF records allow a sender to specify the list of IPs allowed to send mail for that domain and allow ESPs to reject messages originating from IPs not listed in the domain's SPF record.

SERP

Search Engine Results Pages

An SERP is a page that appears after a user enters a query into a search engine. The page displays a list of relevant results to the query, including organic pages and sponsored ads.

SMPT

Simple Mail Transfer Protocol

SMTP is an Internet standard communication protocol or application mail servers use to send, receive, and relay outgoing emails between senders and receivers.

Soft Bounce

An often temporary failed delivery error message.

A soft bounce is an error classification received from a mailbox provider when an email send attempt fails to deliver to a real email address. This is often a temporary error caused by several possible factors, such as the user’s mailbox being full or the mailbox provider receiving too many emails at once. These emails can be sent again at a different date and/or time.

Depending on the error message, best practice is to remove this subscriber after 3 - 5 soft bounces.

T – Z

TCP/IP

Transmission Control Protocol/Internet Protocol

TCP/IP is a framework for organizing the set of communication protocols used in the Internet and similar computer networks according to functional criteria.

Throttling

A timely limit on the number of outbound emails sends.

The practice of regulating how many email messages a sender deploys to one mailbox provider or mail server at a time. Some mailbox providers bounce emails if they receive too many messages.

Unknown User

The email address is invalid.

An unknown user is a hard bounce error code generated by a mailbox provider when an email address is not registered in its system.

UTM

Urchin Traffic Monitor

UTM parameters are short snippets of code added to the end of a URL to help you track information about where someone came from—the referring domain—and what they clicked on to get there.

Whitelist

A list of reputable email addresses allowed to bypass reputation and spam scans.

The opposite of a blacklist, a whitelist is a record of senders who meet established standards for reputation, engagement, and sending practices, thus proving themselves to be legitimate and responsible senders.

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