The initialism WTF can refer to:

• The World Taekwondo Federation, http://www.wtf.org/
• Working Title Films, a United Kingdom film production company.
• An initialism for "What the fuck?" in internet slang, Official site. Other, less frequently used meanings include: "Who/Where/Why/When the fuck?" It has been said that this meaning is sometimes used in military parlance, expressed in the NATO phonetic alphabet as "Whiskey Tango Foxtrot".
• wtf is also the name of a command line acronym database, whose meaning is also "what the fuck?". It first appeared in NetBSD 1.5, see e.g. http://netbsd.gw.com/cgi-bin/man-cgi?wtf++NetBSD-current