why html is a markup language code example

Example 1: what is markup language

A markup language is a computer language that uses tags to define elements within a document. It is human-readable, meaning markup files contain standard words, rather than typical programming syntax. While several markup languages exist, the two most popular are HTML and XML.

Example 2: what is html

HYPER-TEXT MARKUP LANGUAGE
Is the standardised markup language (a subset of XML) that 
defines the layout of a webpage. 
HTML has no functional properties, other languages such as 
JavaScript must be used in order to manipulate the layout
and perform HTTP requests.
CSS (Cascading Style Sheets) is commonly used to style the
elements in the layout.