HTML Heading are used to give headings of paragraphs and articles on the web page.
Headings are define by <h1>, <h2>, <h3>, <h4>, <h5>, <h6> tags.
<h1> shows the most important heading.
<h6> shows the least important heading.
<h6> to <h1> tags defines the progressively increasing of importance of Heading and Size.
Heading are also important for Search Engine (like Google, Bing, Yandex etc.) to index and rank the web pages and it increase the SEO of Website.
The text written in between <h1> opening and </h1> closing tag makes the text bold and increases the size of the text which increases the importance of the text as compared to other normal text.
Similarly <h6> tag does the same thing.
The only difference between <h1> tag and <h6> tag is the sizes of the text, when we implement <h1> tag it makes the size of the text bigger than the <h6> tag which shows that <h1> tag is use to give more important heading as compare to <h6> tag.
Run the code to see the effect.