Answer
HTML5 semantic tags define the function and the category of your text, simplifying the work for browsers and search engines, as well as developers.
HTML5 offers new semantic elements to define different parts of a web page:
<article><aside><details><figcaption><figure><footer><header><main><mark><nav><section><summary><time>
Syntax:
<!DOCTYPE html>
<html>
<head>
<meta charset = "utf-8"/>
<title>...</title>
</head>
<body>
<header>...</header>
<nav>...</nav>
<article>
<section>
...
</section>
</article>
<aside>...</aside>
<footer>...</footer>
</body>
</html>