Document File Formats:-
DOC – Microsoft Word document
DOCX – Office Open XML Text document or Microsoft Office Word 2007 for Windows/2008 for Mac
PDF – Portable Document Format
HTML – HyperText Markup Language (.html, .htm)
Graphic File Formats:-
GIF – Graphics Interchange Format
JPEG(.jpg or .jpeg) – Joint Photographic Experts Group
PNG – Portable Network Graphic
Sound File Format:-
Words from the author: "I always thought full form of MP3 is "Music Player 3" but is isnt :)"
MP3 - MPEG Audio Layer 3
Video File Formats:-
3GP - Third Generation Partnership Project(3GPP)
MPEG - Moving Picture Experts Group
AVI - Audio Video Interleave
WMV – Windows Media Video
