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.