Anyone know what these tags will do in a KF8 book

[user743]

<menu>
Is this a pop-up menu? if yes, can i make a submenu and links inside?

<hgroup>
??

<header>
Does this get attached to the top of every page?

<section>
What's the difference between this and splitting the html into two?

[Doitsu]

AFAIK, even though <menu>, <hgroup>, <header> and section are listed as supported tags in the Kindle Publishing Guidelines (KPG), you cannot use them to create interactive Kindle content. IMHO, the tech writer in charge of the KPG most likely simply copied and pasted most tag definitions from Quackit without fully understanding them. They even included deprecated tags such as <hgroup>. They also included <output> in the official list, which is rather pointless without <input>, which is not on the list.

OTOH, several CSS3 elements that aren't officially supported according to the KPG, actually work on all currently supported Kindles.
You can, for example, create quizzes with answers formatted as upside down text using 2D Transforms.

[user743]

they do look identical (with some removed) but it doesn't have <hgroup> in the list so it was obviously added intentionally.

…

i dont now what the definition of "interactive content" is. I'm not trying to make forum style content with <menu>. rather i wont to make a pop up table of contents with submenus and links to the rest of the book.

[Doitsu]

Originally Posted by user743

I'm not trying to make forum style content with <menu>. rather i wont to make a pop up table of contents with submenus and links to the rest of the book.

Unfortunately, the only kind of popups that you can generate in Kindle books are footnotes. However, they're heuristically generated and only supported by the latest generation of PW2 models. For more information, see this thread.