The HTML element will be defined by the starting/<> tag . If the element has content, it will end with a closing tag</>, where the element name will be written inside both of them .

The p , h1, and div are all HTML element. There are some HTML elements which don’t need to be closed, for example : <img/>, <hr /> and <br /> elements. These are known as void elements.
There’s also nested elements !!

HTML elements can be nested where elements in an html document can contain other elements .most HTML documents are consist of nested HTML elements.
Good news come with those with patience , that went through the whole blog.
Rejoice !! HTML is not case sensitive . so <P> will be the same as <p> . Very merciful when your writing code , and your tired after working many hours !
Citation : https://www.w3schools.com/html/html_elements.asp , https://www.tutorialspoint.com/html/html_elements.htm