If you’ve ever used or heard of Schema.org to mark up, you’ll helping search engines (like Google,Yahoo,Bing) Understand your content. Schema markup is a great way to help your website stand out from your SEO competitors by creating more relevant, rich and attractive search results.

Schema markup is not only used in website but also email.
Yes,Now you enrich your email with Schema tag.This will include adding quick actions to your emails, triggering Google Now cards.Emails with markup appear in Google Search results when users search for meeting, flights and events.

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Benefits Of Email Markups 

Why should you use Email Markup?

When you offer actions right in the email inbox,user can simply clicks a button to take immediate action.This is a huge time saver and cuts out the hassle of opening the email,visiting your site and then click on button.Adding email markup language(QUICK ACTIONS) in the actual subject line can boost yours key metric and as a result, your revenues and leads generated, too.

Guide for Email Markup

Getting started with Schema.org email markup

First, you have to be registered with Google. The main purpose of this is to make sure that the emails you’ll be sending out are secure and not spam.
You can add email markups into your email in two formats  Microdata and JSON-LD.