html5 - div-s inside header or conversly? -

i have question html5-markup: div-s should placed inside tag header, article, etc. or conversely - html5-tags inside div-s? point of view of semantics.

for example:

<article>    <div class="noise">       ... here ...    </div> </article> 

or

<div class="noise">   <article>        ... here ...   </article> </div> 

i need help

that entirely depends on want do, neither more correct per se. example given i'd suggest:

<article class="noise">     ... </article>