1. HTML boilerplate: This is the basic html boilerplate code 
    
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
        <!-- Body -->
</body>
</html>

    2. * Headings: There are six heading available in HTML, H1 is the largest among all, and H6 is smallest
  2. <h1> Tag 
    <h1>Heading 1</h1>
  3. <h2> Tag 
    <h2>Heading 2</h2>

    4. * Container:
  4. div tag 
    <div>This is div block</div>
  5. span tag 
    <span>This is span block</span>
  6. pre tag 
    <pre>Hello World</pre>
  7. code tag 
    <code>
import python
</code>

    8. * Text Formatting: Text formatting tags are used to format text or data of HTML documents. You cna do certain things like creating italic, bold ,strong to make your document look more attractive and understandable.
  8. <b> tag 
    <b>This is bold text</b>
  9. <strong> tag 
    <sub>I'am important text</sub>
  10. <sub> tag 
    <sub>Subscript</sub>

    11. * List : List can be either numerical, alphabetic, bullet, or other symbols.
  11. <ol> tag 
    <ol>
    <li>Data 1</li>
    <li>Data 2</li>
    <li>Data 3</li>
</ol>
  12. <ul> tag 
    <ul>
    <li>Data 1</li>
    <li>Data 2</li>
</ul>

    13. * Media: media is anything that is present in digital form such as image, video, audio,etc.
  13. <img> tag 
    <img src="Source_of_image" alt="Alternate text">
  14. <video> tag 
    <video width="480" height="320" controls>
<source src="demo_move.mp4" type="video/mp4">
Your browser does not support video tag.
<video>

    15. * Form :
  15. <sample form> 
    <form>
<label for="fname">First name:</label><br>
<input type="text" id="fname" name="fname"><br>
<label for="lname">Last name:</label><br>
<input type="text" id="lname" name="lname">
</form>
    16. * Characters and Symbols: some symbols are not directly present on the keyboard, but there are some ways to use them in HTML documents.
  16. Copyright Symbol (©) 
    &copy;
  17. Less than (<) 
    &lt;
  18. Dollar ($) 
    &dollar;
  19. Random Text 
    Lorem ipsum dolor sit amet consectetur adipisicing elit. Temporibus suscipit quaerat eos voluptate, ratione blanditiis nulla quibusdam explicabo iusto praesentium laborum distinctio? Quo optio voluptates atque ut voluptatem maiores rerum.
  20. <section> tag 
    <section>This is section<section>