<!DOCTYPE html>
<html lang="en"> <!-- sets language to english -->
<!-- <head>, <body>, etc. contents-->
</html>
The HTML lang attribute is used to identify the language of text content on the web. This information helps search engines return language specific results, and it is also used by screen readers that switch language profiles to provide the correct accent and pronunciation
Syntax
<element lang="language_code">
Example
Some French text in a paragraph:
<p lang="fr">Ceci est un paragraphe.</p>
<html lang="en">
<body>
<h1>Detects you are using english</h1>
</body>
</html>
Yeah actually it's not a programming language but it is a markup language.