What is <nav>?

Question

I mean it is necessary?..

Answer 1

it contains the navigable section of your web site in the html5 structure

Answer 2

The <nav> element represents the navigation for a document. The navigation can be within the document or to other documents, but it is important to notice, that not all links in a document should be marked up with the <nav> element.

<nav>
<ul>
<li><a
href="home.html" >Home</a></li>
...
</ul>
</nav>

Answer 3

<nav> is just for making our job easy. It is not necessary. You can use some <div> tags in the body (maybe under <header>) and make a nav too.
You can see a navigation bar in many sites around the web and it's where they put some links (and lists) to their important pages.

Answer 4

<nav> is an html5 element for creating navigation links