Web Design with HTML and CSS Digital Classroom
by Jeremy Osborn, Jennifer Smith, AGI Creative Team

Lesson 9: Browser Compatibility
Browser testing is necessary because different web browsers render HTML and CSS code differently. In this lesson, learn to determine how much testing is necessary for any given project, as well as techniques for fixing browser issues or incompatibilities.
What you’ll learn in this lesson:
• Testing your browser
• Using different browser testing tools
• Using conditional comments with Internet Explorer
• Dealing with future browser compatibility problems
Starting up
You will work with several files from the web09lessons folder in this lesson. Make sure you have loaded the weblessons folder onto your hard-drive from www.digitalclassroombooks.com/webdesign. See “Loading lesson files” in the Starting Up section of this book.
![]() |
Why browser testing is important
A web browser is a program that renders HTML, CSS, and JavaScript files according to a set of rules built into the application. Although web browser manufacturers use the recommended guidelines of the Word Wide Web Consortium’s ...
