HTML vs XML

Question

HTML and XML are markup language . What is the difference and when to use it ?

Answer 1

HTML
1) Language for Presentation
2) Predefined Tags

XML
1) Language for storage/transfer of Data
2) User-defined Tags

Answer 2

XML was designed to carry data - with the focus on what data is
HTML was designed to display data - with the focus on how data looks
XML tags are not predefined like HTML tags

Answer 3

Check my answer in your previous question, and do a search in Q&A discussions section about xml and xhtml: this question was already asked/answered a lot ^^

Answer 4

HTML for classic and web main
XML for sitemap is a main use

Alternative uses of XML is on REST API for maintain compatibility with old systems, currently JSON is the standard for interchange data.

In other scenario on desktop apps xml is extended use for save user prefs.

Use HTML and JSON and forget XML if web is you main business ;)