User blog comment:Alchimous/The Curse of Span/@comment-4954747-20121214033425/@comment-24180511-20121214052204

Span tags are data that hides in the source code, changing things in ways that are useless and should not be there. It most often occurs when people take things from programs like word which saves all this in the background. Make a ton of fancy text in word and look at the file in notepad, you'll see.