I was wondering if it was considered more professional to write a website in strict xhtml rather than transitional.
Is it something that should be done as you advance as a web developer, or is it irrelevant?
With the possible exception of the (rarely needed) start attribute, the difference between Strict and Transitional boils down to "Things you should not have used since Netscape 4 stopped being a dominant browser".
So, the question is a tricky one as, if you learned HTML this side of the millennium, you shouldn't have been using Transitional in the first place (now let us have a minutes silence as we lament the poor quality of over-popular tutorials (such as one from an organization that gets a lot of glory reflected off the W3C due to its similar name … and I'm ranting, so I'll stop now).