Answer :
It is true that many web sites use cascading style sheets (css) to define the design and layout of web pages, and extensible markup language (xml) to define the content, and hypertext mark-up language to join the content.
In order to govern a text document's structure, formatting, or relationships between its sections, a text-encoding system called markup language is used. Markup is frequently used to modify how a document is displayed or to enhance its content in order to speed up automated processing.
A markup language is a collection of guidelines that specify what markup information can be used in a document and how it should be mixed with the content to make it easier for both people and computer systems to utilize. The concept and phrase originated from the "marking up" of paper manuscripts (i.e., the revision directions by editors), which are customarily put on writers' manuscripts with a red pen or blue pencil.
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