01_Intro-to-nodejs.md

Introduction to Node.js

What is Node.js?

• Node.js is an open-source, cross-platform Javascript runtime environment built on Chrome's V8 Javascript engine.
• Node.js has an event-driven architecture capable of asynchronous I/O (Non Blocking I/O).
• Node.js enables Javascript to run anywhere (servers, desktops, embedded systems etc), not just in the browser.
• Node.js can be used to create servers, web apps, command line tools and many more.
• Node.js is maintained by OpenJS Foundation.

Why Node.js was created?

• Before Node.js, most servers relied on blocking I/O (like Apache Http Server).
• The goal was to create a server that utilizes Non-Blocking I/O.

History of Node.js?

2009

• Node.js was developed by Ryan Dahl in 2009.
• Initially SpiderMonkey was chosen as the Javascript engine, but it was soon replaced with V8.
• At that time, Joyent was working on a similar project and invited Ryan Dahl to join their company and develop Node.js.
• Node.js was initially named as Web.js, reflecting its use for creating web servers. It was later renamed to Node.js.

2010

• NPM was developed by Isaac Schlueter in 2010.

2011

• Windows support was added. Previously, it only supported linux and macos.
• Joyent + Microsoft together developed the windows version.

2012

• Ryan Dahl stepped away from the Node.js project, and Isaac Schlueter took over as the project lead.

2014

• io.js was introduced which was a fork of Node.js.
• io.js was created with the intention to accelerate the development and predicted releases of code under an open governance model. Since Node.js was governed by Joyent, io.js was created as an alternative.

2015

• The Node.js foundation was established as an independent entity to over see the development and releases of Node.js.
• Node.js foundation combined the releases of Node.js and io.js into a single code base.

2019

• JS Foundation and Node.js foundation merged together to form OpenJS Foundation.

Appendix

What is NPM?

(GIST)

• NPM is the standard package manager for Node.js.
• It started as a way to download and manage dependencies for Node.js.
• Yarn, pnpm are alternatives to npm cli.
• NPM manages dependencies using the package.json & package-lock.json files.

Blocking I/O vs Non-Blocking I/O

(GIST)

• Blocking I/O is an I/O operation that prevents the execution of the program from proceeding until the operation is complete (i.e., the CPU remains idle until the I/O operation finishes).
• Non-Blocking I/O allows a program to continue executing other tasks while the I/O operation is in progress, rather than waiting for it to complete.

Check more on Node.js

• Node.js: The Documentary | An origin story
• Ryan Dahl: Original Node.js presentation

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