Email marketing is a complex subject, and we’re not shy to admit this. It’s not easy to create campaigns,  measure their results, test new features, and automate messages in a flow… Many things are involved in even the most straightforward of campaigns. So, in this short glossary, we’ll define a few main concepts that you should be aware of if you want to dip your toes into the water.

If you’re an email marketing beginner, this list will offer you precious insights into how you should proceed. If you already have some experience with email flows, drips and automations, you will also find relevant knowledge in this article. 📝

Email Marketing Glossary

A/B Testing

This one is a classic in digital marketing. A/B testing means sending your recipients two versions of the same content to gather which one is more effective. We recommend doing this test with about 30% of your audience, half to each version. Then, send the winning message to the 70% left.

Try this with different segments in your audience. This technique will provide better results that have been proven by experience.

Acceptance Rate

There is a limbo between sending an email and it being delivered to the inbox. Acceptance rate refers to the percentage of emails sent that were accepted by the server. This does not mean that they were delivered, but gives you an insight into what could be wrong if you’re not landing in the inbox.


If your spam score is high, you might find yourself in a blacklist. To sum up, a blacklist registers senders who are blocked from sending email broadcasts. This destroys the sender’s email deliverability, and it usually does not happen unless they are sending unsolicited emails or scamming email users. 🥷

Bounce Rate

This rate measures the percentage of emails that were not delivered – meaning, they bounced from the recipient’s inbox. An acceptable bounce rate is under 5%. There can also be soft bounces or hard bounces, which we will discuss later in this glossary.

Email marketing


CAN-SPAM is a law passed in the United States in 2003 that defines acceptable practices for email marketing. 🥫 Overall, it establishes that you need permission to send commercial emails, and that every recipient can leave a mailing list at any time. It attributes fines for spammers and unsolicited email senders. Some offenses can actually land perpetrators in prison.

CTR – Click-Through Rate

This metric measures the number of clicks on links in your email messages, divided by the number of opened emails from your broadcast. This results in a percentage that you can use to measure how efficient your copy is.

Conversion Rate

Conversion Rate measures the percentage of readers that actually performed a desired action. A conversion can mean subscribing to a mailing list, starting a trial for a service, purchasing a product and similar actions that require an investment (in time, money, or both) from the reader.

Dedicated IP

When you are sending an email broadcast, your results can be dwarfed by the bad reputation of other senders that are using the same IP. This results from a shared IP between different customers of an email marketing service.

If you have a dedicated IP, you can ensure that your reputation depends solely on your content and practices, which is a lot better than a shared IP. However, this usually comes at an extra cost.

Double Opt-In

This is the ideal way to add contacts to your mailing list. Double opt-in means that not only the user added their email address to a form to receive updates, but that they also clicked on a button in a confirmation email. 🙋

The double opt-in makes sure that every one who subscribes to your mailing list really wants to. We recommend always setting up double opt-in on your email marketing campaigns. This ensures that you comply with data protection laws and conventions such as CAN-SPAM.

Email Campaign

An email campaign is a sequence of emails set to be sent to a specific group of recipients in your list. Usually, these recipients have something in common with each other, like a demographic trait or an interest in a specific type of product.

Hard Bounce

A hard bounce happens when delivery is not possible due to a permanent issue: either when the user has blocked your email, or the email address is wrong or non-existent. This is different from a soft bounce, which is temporary – but we’ll get to that later.

IP Warmup

When sending an email to a large quantity of users, it is recommended to warm up the IP. What does this mean? Warming up an IP means to message progressively increasing groups of users until you actually start sending to the whole mailing list.

This is recommended when you have a new provider and want to start sending to a large mailing list. Warming up avoids your IP from being blocked and your messages considered spam. 🔥

Landing Page

Landing Pages can be created for various purposes, usually to host forms, CTAs (calls to action) buttons, and other instances in which users can convert.

We already explained what a conversion is: the target action for the user to complete, such as a subscription, a purchase, requesting more information from the seller…

A landing page is usually associated with a campaign: the first goal for a campaign is to get users to click on the link that takes them to the landing page. In that page, more information is provided about the target offer. These details will help users decide on what to do.

Email Marketing

List Segmentation

You should segment your mailing list for a better performance. Segmentation allows you to send a message that targets a group of people. These groups are called segments.

By splitting your mailing list into segments, you make sure that you are emailing the right people at the right time.

Segments can be created according to demographics, behavior, previous purchases, and many other factors. 💵

Open Rate

The open rate measures the percentage of emails opened. It is calculated by dividing the total number of opens against the total number of emails sent.


Opting in is subscribing to a mailing list. As we mentioned previously, double opt-in is recommended for best deliverability.


If opting in is subscribing to a list, opting out is unsubscribing. Every email you send to a user should have a link to unsubscribe from all future communications.

Unsubscribing means that the recipient refuses to receive any more emails (or messages through other channels, such as SMS) from the sender. 💻

You can also opt-out of specific types of emails from the same sender. The user might not be interested in newsletters, but want to receive product launch notifications. It’s important to add this option to the emails you send to your list.


Personalization in email marketing is using data you already have from a user in order to adapt the content that is specific to them. This could include using fields like name, email address, past purchases… This content will be unique to each user, according to previously established rules.

You can personalize your content in Platformly using content snippets.

Plain Text Emails

When designing an email, you can use HTML for your formatting. Emails with HTML are usually more visually appealing, but you can also create emails that only contain text. Plain text emails are usually better when it comes to accessibility, and they make sure that your content will not look broken in specific email clients. 📃

You can also create an email in HTML and offer the possibility of reading the email in plain text.

Shared IP

We’ve mentioned dedicated IPs previously. The opposite of a dedicated IP is a shared IP.

There are some advantages to using this kind of IP.

If you start emailing from a shared IP, you already have a set reputation – this might help if you don’t have the time to warm it up. Also, shared IPs are a lot cheaper than using a dedicated IP.

If you are using an email marketing service that offers good deliverability, you can use a shared IP with confidence.

Single Opt-In

A single opt-in only asks for the email address of the user and does not use a confirmation email. This practice has several disadvantages.

First of all, anyone can add an email address to your mailing list, which is not safe at all. Also, if the user subscribes by accident and/or is not really interested in your content, they’ll either unsubscribe or, worse, mark your emails as spam. This will damage your reputation as a sender and could ruin all your email marketing efforts by getting you blacklisted.

Audience Segmentation

Soft Bounce

Soft bounces, unlike hard bounces, result from temporary issues. An example of this could be a full inbox, or an unavailable server.


This is a commonly used term in email marketing. It is estimated that 90% of all sent emails are spam. But what is it really?

Spam is email that wasn’t solicited by the recipient, usually with a commercial intent. Readers can mark any email as spam, but the more it happens, the worse the sender reputation gets. Usually sending unsolicited emails will end up putting your sender email address in a black list. 📧


Subscribing means that the user has chosen to receive communications from a specific sender. These communications can be offers, new products, newsletters, and many other kinds of email marketing messages.


The opposite of blacklisting. You can ask your subscribers to whitelist your emails, which will mean you’ll always land in the inbox for them. Of course, it has to be the subscriber whitelisting you and not the opposite.

Getting whitelisted is a great sign of trust from your readers.

Wrapping Up

These are the main concepts you should know about when starting an email marketing campaign or an automation.

If you’re no longer a beginner in email marketing, we think you’ll like this article about email deliverability.

What do you think? Did we miss something? Use the comment box or reach out to us on Facebook, LinkedIn or Twitter. Happy emailing!

About Author

Deeply passionate about writing, copy, and social media. Digital Marketing Assistant at Platformly.


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