Backend

From Dndwiki

Back End and Server Side coding is the more advanced forms of making websites that enables more features than the basic website would need. Unlike 'scripting' - which is languages like JavaScript - Server Side programming are run before the page is displayed allowing the user to only get the data that they requested.

Websites that will look different for each user, or can display different content with the same URL are usually use back end or server side programming.