HTML elements are always enclosed in opening and closing tags.
Example:
For heading:
[html]
Heading
[/html]
It is imperative to use the closing tag.However ,there are some HTML elements that don’t need a closing tag such as <img…/>, <hr /> and <br />.These are known as void elements.
Nested HTML elements
[html]
Heading
paragraphitalic
[/html]