Here are various html elements which has been added to html5, some of the important elements are listed bellow:

1. . <header>

   This html element is used for define the header section of the html page.

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   <header>
       <p>this is header</p>
   </header>

   <header>
       <p>this is header</p>
   </header>

2. . <footer>

   This html element is used for define the footer section of the html page.

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   <footer>
       <p>this is footer</p>
   </footer>

   <footer>
       <p>this is footer</p>
   </footer>

3. . <nav>

   This html element is used for navigation propose.

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   <nav>
       <a href="#">first navigation</a> |
       <a href="#">second navigation</a> |
   </nav>

   <nav>
       <a href="#">first navigation</a> |
       <a href="#">second navigation</a> |
   </nav>

4. . <figure>

   This html element is used for showing diagrams, photos, code etc. in the html page.

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   <figure>
     <img src="myImage.jpg" alt="Imagek" width="100" height="200">
   </figure>

   <figure>
     <img src="myImage.jpg" alt="Imagek" width="100" height="200">
   </figure>
   

5. . <article>

   This html element is used for articles (a special way of representing text in html page).

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   <article>
       <p>this is article</p>
   </article>

   <article>
       <p>this is article</p>
   </article>

6. . <details>

   This html element is used for showing details that is the extra information about something and it also allows the use to show or hide this particular section in the html page.

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   <details>
     <summary>Click here to show details.</summary>
     <p> This is details.</p>
   </details>

   <details>
     <summary>Click here to show details.</summary>
     <p> This is details.</p>
   </details>

7. . <time>

   This html element is used for showing date and time in the html page.

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   <time datetime="2015-08-15 20:00">Independence day</time>

   <time datetime="2015-08-15 20:00">Independence day</time>
   

8. . <output>

   This html element is used for showing output of any function on the html page.

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   <output name="result" for="idOfOtherElement"></output>

   <output name="result" for="idOfOtherElement"></output>
   

9. . <aside>

   This html element is used for showing the information which correlated to the html page.

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   <aside>
   <p>aside element </p>
   </output>

   <aside>
   <p>aside element </p>
   </output>
   

10. . <meter>

    This html element is used for showing measurements in the html page

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    <meter value="6" min="5" max="7"></meter>

    <meter value="6" min="5" max="7"></meter>
    

11. . <video>

    This html element is used for render video in the html page

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    <video width="200" height="100" controls>
      <source src="video.mp4" type="video/mp4">
      Your browser does not support the video tag.
    </video>

    <video width="200" height="100" controls>
      <source src="video.mp4" type="video/mp4">
      Your browser does not support the video tag.
    </video>
    

12. . <audio>

    This html element is used for render audio in the html page

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    <audio width="200" height="100" controls>
      <source src="horse.mp3" type="audio/mpeg">
      Your browser does not support the audio tag.
    </audio>

    <audio width="200" height="100" controls>
      <source src="horse.mp3" type="audio/mpeg">
      Your browser does not support the audio tag.
    </audio>