Sites With Reusable Snippets of HTML, CSS, and Javascript

Codepen

• http://codepen.io/

CodePen is a playground for the front end web. Show off your latest creation and get feedback. Build a test case for that pesky bug. Find example design patterns and inspiration for your projects.

Editors

Brackets

• http://brackets.io/

A modern, open source text editor that understands web design.

There are reports that this is faster than Atom.

Frontend Libraries

Keyboard Controls

• Mousetrap: https://craig.is/killing/mice "A simple library for handling keyboard shortcuts in Javascript."
• jQuery Hotkeys: https://github.com/jeresig/jquery.hotkeys "jQuery Hotkeys lets you watch for keyboard events anywhere in your code supporting almost any key combination."
• Shortcut.js: http://www.mattytemple.com/projects/shortcut-js/ "shortcut.js is a JavaScript file that enables keyboard shortcuts in any web application."

Link here.