One of the joys of creating new templates and web pages is the instant gratification that comes with viewing a new gem in a browser (or multiple browsers) for the first time. It is not unlike seeing a new creature born...and not unlike the parent of a new creature, one of the first things checked, is to see if all the parts are in working order. That's not the best analogy, I'll admit...no one turns a web page upside down checking things out. And before I get beat up by those who endured childbirth I'll explain.
Beneath all the text, images, and general layout of a web page is a bunch of geeky looking code. For those who work toward complying with web standards that make those pages available on browsers around the world, there are validation services. I lean toward using the W3C Markup Validation Service primarily because it comes from a body (W3C) that many feel to be most dedicated to standards in coding. The process is simple. Go to the validation service and type in the full URL of the page you want checked...and tah-dah, you get instant feedback on your code. Can't you just feel the excitement??
All of that to say. I am frustrated with some of my own coding... even here on the page you are reading. With 30 minutes of tweaking, the number of validation errors has dropped from 40 down to 18. AKKK... 18 errors!!! So don't look too hard, this baby has flaws...oh, the disgrace.