Deno is a modern, secure runtime for JavaScript and TypeScript, created by Ryan Dahl — the same developer who originally built Node.js.

It was designed to fix some of Node.js’s early design issues. Key features include:

• Built-in TypeScript support — no separate compiler needed.
• Secure by default — no file, network, or environment access unless explicitly allowed.
• Single executable — everything (runtime, package manager, formatter, linter, test runner) is included.
• Uses modern web standards — like ES modules and browser-compatible APIs.

In short — Deno is a secure, modern alternative to Node.js for running JavaScript and TypeScript outside the browser.