Practice: Checking HTML5 Files

The W3C Nu HTML Checker — https://validator.w3.org/nu/ — is a useful tool for checking your HTML5 code.  

This online tool offers three mechanisms to check HTML code:

1. address (providing a URL)
2. file upload
3. text input

You get to practice all three methods with this quiz!  

Note:  I usually find that I use the "text input" method quite a bit while developing -- it is easy to "select all" in your editor, copy, and then paste into the Nu HTML Checker.  Then I do a final check using the "address" after publishing the page.  You'll find a flow that works for you, but if you're looking for a place to start, try mine out!