What is Liquid?

Liquid is a template engine that enables you to combine dynamic content with static content. It was originally created by Shopify co-founder Tobias Lütke. Written in Ruby, Liquid was built to create a sort of bridge between an HTML file and a data store—allowing Shopify’s users to build customized themes for different customers and keep sensitive data secure when personalizing content.    

Liquid is an open source language, which means that anyone can modify it and make new versions—and a lot of folks have! Today, it’s in wide usage for web and email, and has developed many “flavors” as developers have molded it to meet their needs.

So if your ESP has a flavor of Liquid (and it probably does!), you can use it to create highly personalized emails. Let’s imagine you run an ecommerce site, Tip Top Pets, and one of your customers just purchased a new dog leash. That purchase will trigger an order confirmation email. 

Most of the content in your confirmation emails will be the same for every customer—some “thank you for your purchase” language, brand images, etc. The code for all that content is static-—that is, it’s the same for every customer. 

But you also want to personalize the content for each individual customer—like including their name, the item they purchased, and maybe some recommendations for related products they might like. Ooh, how about a special coupon?! The more personal you can be, the more engagement you’ll get. That means your email needs dynamic content that’s unique to this customer and this purchase—and you can use Liquid to add that dynamic content with code that pulls info about each individual from your data source.