For better info about div tag you should visit the following link
No, no they shouldn't... since W3Schools has absolutely nothing to do with the W3C, is filled with incomplete and misleading information, and on the whole is a bunch of halfwit garbage.
Or not... huh... site is down.
In any case, DIV and SPAN are both simple -- they are 'semantically neutral' containers, which is to say they do not impart meaning to what you are wrapping other than "This MAY receive an unspecified style". You use them to group elements into groups, or has hooks for presentation without saying what that presentation is.
Which is why as a rule of thumb you shouldn't be adding DIV or SPAN until AFTER you've written your base semantic markup and have started applying your CSS to it -- remember, PROPERLY written HTML shouldn't be saying ANYWHERE inside it what things look like, it should say what things ARE, which is why getting all your headings, paragraphs, and lists in place BEFORE you start screwing around with making a layout is important.
Assuming you're using semantic markup and separation of presentation from content; though honestly I'm tempted to STOP calling it that and call it what it REALLY is... USING HTML PROPERLY.
Which the vast majority of people sleazing out websites don't do.