Are you creating text in Microsoft Word and then copying and pasting it into a web page? If so, don’t. And here is the reason why.
Microsoft Word creates all sorts of formatting clutter in the source code of your page. And that is not good. It’s easy enough to get around the problem. Some html creating programs have a Word-cleaning tool built in that you can use. But I’ve found it much easier to just create the text in wordpad and then copy that text onto the webpage.
You want as little formatting clutter as possible in your source code. This is just one simple way to cut down on it.