JavaScript Fundamentals & Web Internals

A curated collection of notes, experiments, examples and small projects that explain how JavaScript, the runtime, the NodeJs, and the web work under the hood.

Focus areas:

• JavaScript core concepts and idioms
• Asynchronous patterns and the event loop
• Node.js runtime internals and simple servers
• Hands-on experiments that reveal real runtime behavior

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Repository overview

Top-level folders and what you'll find in them:

• assets/ — supplemental images, diagrams and media used across docs and examples.
• core-js/ — bite-sized JS examples and experiments (arrays, promises, this, prototypes, etc.).
• docs/ — detailed conceptual notes: event-loop, async patterns, HTTP, Node internals and more.
• node-basics/ — small Node.js examples and notes.
• node-express-server/ — a small Express-based server skeleton (starter code).
• node-http-server/ — minimal examples using Node's built-in http module.
• playground/ — quick scripts to try interesting runtime behavior locally.
• projects/ — small sample projects

Also check:

• package.json — project metadata / scripts.

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Quick start

Requirements:

• Node.js (LTS recommended)

Run a simple example or experiment:

1. From repo root, run a playground script:

node playground/event-loop-order.js

2. Run a small server (many examples include index.js):

node node-http-server/index.js
# or
node node-express-server/index.js

3. Alternatively use npm scripts defined in package.json:

npm run http             # start minimal http server
npm run express          # start express skeleton
npm run start-01         # sample project-01
npm run start-02         # sample project-02 with nodemon
npm run start-url        # short-url project
npm run bot              # discord-bot
npm run start-image-uploader
npm run start-blog-app-server
npm run start-chat-app-server

4. Open the docs for conceptual reading: see docs/ for write-ups on event loop, async/await, HTTP details and more.

Note: individual projects may require npm install if they use dependencies (check the project folder).

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Projects & examples

• short-url/ — small full-stack example (routes, views, MongoDB connection helper).
• projects/project-01/, projects/project-02/ — sample app code and data to explore.
• projects/blog-app/ — simple blogging platform with auth, CRUD and EJS views.
• projects/chat-app/ — realtime chat server using Socket.io.
• projects/discord-bot/ — Discord.js bot skeleton.
• projects/image-uploader/ — file upload/demo with Multer.

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