Check out example codes for "html section tag". It will help you in understanding the concepts better.

Code Example 1

Section tag defines the section of documents such as chapters, headers, footers
or any other sections. The section tag divides the content into section and 
subsections. ... Section tag grouped the generic block of related contents.

Code Example 2

<section>
  <h1>Heading</h1>
  <p>Bunch of awesome content</p>
</section>

Code Example 3

<html>
<head></head>
<body>
    <header></header>
    <section>
        <h1>ffffff</h1>
        <div>
            <span></span>
        </div>
        <div></div>
    </section>
    <footer></footer>
</body>
</html>

Code Example 4

<section id="header"> Name of section
	<div class="container">
		<div class="row">
			<div class="col-xs-12"></div>
		</div>
	</div> 
</section>

<section id="main-content"> Name of section
	<div class="container">
		<div class="row">
			<div class="col-xs-6"></div>
			<div class="col-xs-6"></div>
		</div>
	</div> 
</section>

<section id="footer"> Name of section
	<div class="container-fluid">
		<div class="row">
			<div class="col-xs-4"></div>
			<div class="col-xs-4"></div>
			<div class="col-xs-4"></div>
		</div>
	</div> 
</section>

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