The tabs structure consists of an unordered list of tabs that have hashes corresponding to tab ids. Then when you click on each tab, only the container with the corresponding tab id will become visible.

Basic

Test 1

Test 2

Test 3

Test 4

<div class="row">
  <div class="col s12">
    <ul class="tabs">
      <li class="tab col s3"><a href="#test1">Test 1</a></li>
      <li class="tab col s3"><a class="active" href="#test2">Test 2</a></li>
      <li class="tab col s3"><a href="#test3">Test 3</a></li>
      <li class="tab col s3"><a href="#test4">Test 4</a></li>
    </ul>
  </div>
  <div id="test1" class="col s12">Test 1</div>
  <div id="test2" class="col s12">Test 2</div>
  <div id="test3" class="col s12">Test 3</div>
  <div id="test4" class="col s12">Test 4</div>
</div>

Preselecting a tab

By default, the first tab is selected. But if this is not what you want, you can preselect a tab by either passing in the hash in the url ex:#test2. Or you can add the class active to the a tag.
<li class="tab col s2"><a class="active" href="#test3">Test 3</a></li>
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Monday, Feb 23, 8:23 pm
Hi, Felicia.
How are you?
John Doe Hi! I am good!
Glad to see you :)
This long text is intended to show how the chat will display it.
John Doe Also, we will send the longest word to show how it will fit in the chat window: Pneumonoultramicroscopicsilicovolcanoconiosis
Friday, Mar 10, 5:07 pm
Hi again!
John Doe Hi! Glad to see you.
I want to add you in my Facebook.
Can you give me your page?
John Doe I do not use Facebook. But you can follow me in Twitter.
It's good idea!
John Doe You can find me here - https://twitter.com/nkdevv