Lesson 1 / 30
What is Node.js?
Learn what Node.js is, how V8 and the single-threaded event loop work, and where Node is used outside the browser.
JavaScript, off the browser
Node.js is a JavaScript runtime built on Chrome's V8 engine. It lets you run JS on servers, in CLI tools, and in build scripts — anywhere, not just a browser tab.
Non-blocking by design
Node uses a single-threaded event loop with non-blocking I/O — it can handle thousands of connections without spawning a thread per request.
One waiter, many tables
Think of Node as a single waiter who never stands idle at one table — they place an order (start an I/O task) and move to the next table while the kitchen works.