HTML tags are like keywords. How the web browser will format and display the content is defined by HTML tags. A web browser can distinguish between HTML content and simple content with the help of tags. HTML tags contain three main parts: the opening tag, the content tag, and the closing tag. But some tags are unclosed tags.
Some examples of HTML tags:
<p> Paragraph Tag </p>
<h2> Heading Tag </h2>
<b> Bold Tag </b>
<i> Italic Tag </i>
<u> Underline Tag</u>