Templating Engines for Dynamic Content

When building web applications with Express, we often need to return HTML customized for each user. While we could build strings of HTML manually or use the res.send() method with static content, that becomes unwieldy very quickly. Instead, we use templating engines—tools that let us generate HTML pages dynamically by embedding variables and logic directly into template files.

In this lesson, we’ll learn how to render dynamic content in Express using two popular templating engines: EJS and Pug. This is especially useful when building apps that need server-rendered pages like dashboards, admin panels, or content-heavy websites.

What’s a templating engine?

Express makes it easy to build dynamic web pages using templating engines, tools that combine data with HTML to generate full web pages on the fly.

Instead of creating a separate HTML file for every page in your app, we can define template files that act like reusable blueprints. We pass in data (like a user’s name or a page title), and the engine fills in the blanks when rendering the final page.