Rodent Regatta

I wish there were a way for me to paste some HTML markup here without it rendering. I’d like for you to see five different sources for the first 8 or 10 lines of supposedly valid web pages. The sources are from:

• a new NoteTab Pro XHTML page
• a new TopStyle XHTML page (I don’t know what I’m doing with this tool)
• Jeffrey Zeldman’s book
• the home page of Brainstorms and Raves
• Elizabeth Castro’s book

They’re all different. They have different line lengths. They have different elements. Some have empty lines in them. It’s all quite confusing. Yet, everything I read tells me these lines of code are absolutely vital.