HTML Entities
HTML entities are a way to write special characters. For example, the superior and inferior characters have a special meaning in HTML. To be able to display them correctly, it is recommended to use the following writing: > and <.
This protection is extended to many characters. They have a numerical entity, such as &38; and a literal entity, such as &, for the ampersand.
Such entities are typical of HTML. They are different in different languages.
PHP uses htmlentities() and html_entities_decode() to convert those characters from and to their entities.
HTML entities are useful in the HTML code, but they are confusing in a text file, which has no special entity.