Merge Tags allow you to personalize your Promote emails by pulling unique data from your synced contacts (first and last name or email address). Instead of sending a newsletter with a headline like: "Hey everyone, check out the latest updates to our site!", you can address each subscriber individually for a more personal approach.
When composing an email, you can add this info into any text in your message using the Merge Tags menu. In this example, we'll use First Name.
Selecting First Name from the list will insert a placeholder that will be replaced in the sent email with each recipient's first name, like this:
There are a number of ways you can utilize this feature to customize your emails - try it out the next time you're sending an update to your subscribers!