- CodePen is an HTML, CSS, and JavaScript code editor in your browser with instant previews of the code you see and write. You can use it to build and show off interesting things you've built, build reduced test cases to troubleshoot with, or collaborate with other front end developers.
- When you use this tool you don’t have to worry about students’ environments differing (operating systems, software, file structure, etc.).
- jsFiddle is a playground for web developers, an online editor for web snippets. It is helpful to isolate bugs and many frameworks are supported.
- Both tools allow you to quickly send code snippets to your students via a unique URL, which is very useful for teachers.