Add Node.js Introduction (#2100)

...developer-roadmap/content/roadmaps/107-nodejs/content/100-nodejs-introduction/readme.md file updated with the appropriate guidelines.

content/roadmaps/107-nodejs/content/100-nodejs-introduction/readme.md

@@ -1 +1,9 @@
-# Nodejs introduction
+# Nodejs introduction
+
+Node.js® is an open source, cross-platform runtime environment and library that is used for running web applications outside the client’s browser.
+
+It is used for server-side programming, and primarily deployed for non-blocking, event-driven servers, such as traditional web sites and back-end API services, but was originally designed with real-time, push-based architectures in mind. Every browser has its own version of a JS engine, and node.js is built on Google Chrome’s V8 JavaScript engine.
+
+<ResourceGroupTitle>Free Content</ResourceGroupTitle>
+<BadgeLink colorScheme='blue' badgeText='Official Website' href='https://nodejs.org/en/'>Official Website</BadgeLink>
+<BadgeLink colorScheme='blue' badgeText='Official Docs' href='https://nodejs.org/en/docs/'>Official Documentation</BadgeLink>