There are six main problems with creating web pages for the Internet:

1. Web standards: Everything starts with international standards from the World Wide Web Consortium (W3C). But every improvement (like CSS) requires new standards.

2. Browsers: Not only new versions, but totally new browsers. Presently (2009) there are some twenty current browsers in use—not to mention their older versioms and discontinued browsers.

3. Compliance: Different browsers conform to different standards. In different ways. And they continually change which standards and especially how they're implemented.

4. Web Languages: Beyond HTML, there's DHTML, XML, etc. etc., including Flash, Javascript and others.

5. Platforms: Not just PCs and MACs (and Linux), now we have mobile devices. And each platform has a variety of operating systems.

6. Code Generators: From full design programs like Adobe Dreamweaver and Microsoft Expression to endless plug-ins, add-ons, and widgets.

In addition, problems are generated because these six continually change—and interact with each other. The combination of these factors massively compounds the situation.