Starter Notes

Updated Feb 11, 2022 ·

Overview

Node.js lets you JavaScript run outside of the browser.

• Runs JavaScript directly on your computer
• Uses the V8 engine (same as Chrome)
• Adds new features like file system access
• Provide features that aren’t available in browsers

This means you can build full programs with JavaScript — not just browser stuff.

Purpose

JavaScript was made for webpages, but Node.js makes it usable anywhere.

• Normally, JavaScript controls things on web pages
• Node.js lets JavaScript run like other programs
• You can build server-side apps with it

It makes JavaScript a flexible tool for full-stack development.

How It Works

Node.js is built on the V8 JavaScript engine.

• V8 compiles JavaScript into machine code
• Machine code is what your computer actually runs
• V8 is written in C++ (but you don’t need to use C++)
• Node.js extends V8 to support more features

The result: JavaScript that works like a regular script or backend language.

Features Added

The browser keeps things secure by limiting what JavaScript can do. Node.js removes some of these limits.

• Can access files on the local file system
• Can work with network connections and databases
• Can build apps, tools, and APIs

Limitations

Node.js doesn’t include browser-specific features.

• No access to the DOM
• No window or document objects

Since Node.js runs on your computer, not in a browser, it doesn’t know about webpages.

Simple Example

Here's a basic example:

// hello.js
console.log("Hello from Node.js!");

Command:

node hello.js

Expected output:

Hello from Node.js!

This confirms Node.js can run JavaScript directly like any normal program.