CSS
Cascading Style Sheets
DTD
Document Type Definition
FBML
Facebook Markup Language
HTML
HyperText Markup Language
JSON
JavaScript Object Notation
MD
Markdown
RSS
Really Simple Syndication
SGML
Standard Generalized Markup Language
XHTML
Extensible HyperText Markup Language
XML
Extensible Markup Language
YAML
YAML Ain’t Markup Language