An open-source, cross-platform runtime environment for developing server-side Web applications, Node.js has been around for just a few years, but has already garnered no small amount of popularity and support. Using the widely used JavaScript language, it helps web developers write lightning-fast applications. Node.js support in Plesk enables you to:
Every customer can now host a Node.js application across all of our plans.
More: https://www.plesk.com/blog/product-technology/node-js-plesk-onyx/