What are built-in HTML tags?

Built in tags are default tags in HTML. Means this tags are not created by user they are directly provided by HTML and used by Web browser this is hard to explain 😁😁😁

There is a huge list of tags. So please go to website below. https://www.w3schools.com/TAGS/default.ASP

I saw them, i wanted to know the meaning of "built-in tags". Thanks! And are there any tags which are not built-in?

Okay, now I understood. Thank you.