HTML entities mean if the developer is used the reserved keyword like greater than, less than, & and another special character. If we are used the reserved keyword then we use the & then the name of the reserved keyword and then the semicolon. Syntax

<p> 5 > 3 </p> this is for greater than

<p> 1 < 3 </p> this is for less than

And another method is = ASCII code used and gives a special character.