The HTML <main> tag specifies main or important content in the document. It can be used only once per page and can't be used as a descendent of <article>, <aside>, <footer>, <header>, <nav> element.
Example
You can try to run the following code to learn how to display the main content in an HTML document −
<!DOCTYPE html> <html> <body> <main> <h1>Learning</h1> <p>Learn to gain experience and try to share your knowledge with others.</p> <article> <h3>Web Development Tutorials</h3> <p>Consist of CSS, HTML, and PHP tutorials for 2nd Semester exams.</p> </article> <article> <h3>Academic Tutorials</h3> <p>Consist of Computer Fundamental, Computer Network tutorials for 1st Semester exams.</p> </article> </main> </body> </html>