Lesson 9: Testing and Debugging

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Creating Websites home

   Introduction to the Web
   Introducing HTML
   Marking up text
   Setting Up
   FTP and FileZilla
   Links and anchors
   Getting some style

Intermediate topics
   Style sheets
   Testing and debugging
   Images and maps
   Audio and video
   Intro to JavaScript
   The DOM and scripting
   Logic and Arrays
   Functions and document.write
   Forms and INPUT
   Other controls
   HTML tables
   Structuring tables
   Scripting w/ tables
   Inline frames
   Loose ends


This video explores how to find and fix errors and problems in your HTML or CSS code:


Note: I strongly suggest you view all our videos in full screen mode: click the icon in the lower right corner of the video area (it shows four arrows pointing to the corners of the screen). When you are done, the Esc ("escape") key returns you to regular mode.


Lesson 9: Testing and Debugging

Click here for the video transcript


Postscript to the video:

Well, putting into practice what I'm preaching here, I learned two lessons:

1. To avoid warning messages from the validator, include lang=en
    (or whatever your language is) within your <html> start tag
    (that is: <html lang=en>)

2. Be sure to include this in your <head>:
         <meta charset=utf-8>


Supplemental materials

    A cumulative summary of the contents of the course so far: Click here to download the cumulative technical summary pdf file


Hands on exercise

The goal here is become comfortable with the online validation tools.

For all the lab pages so far: Validate the HTML and CSS then:

make any corrections needed to clear up the errors.

If time and interest permit, try introducing errors then analyzing the messages from the validators


This bonus video discusses the cache and how to clear it:

  • What is the cache?
  • Why do you need to clear it?
  • How do you clear it?
  • Demo video for Firefox, Chrome, Opera, and Microsoft Edge browsers


Lesson 9: Testing and debugging
bonus video: The Cache

Click here for the video transcript


Hands on exercise

Their is no formal hands on lab here, but you might make sure you can clear the cache on your browser.


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