General Agreement on Tariffs and Trade GATT Central Intelligence Agency CIA roentgenium Rg general packet radio service GPRS graphics interchange format GIF wireless application protocol WAP portable document format PDF personal digital assistant PDA multimedia message service MMS advanced mobile phone service AMPS global system for mobile communications GSM american standard code for information interchange ASCII digital audio tape DAT global positioning system GPS Internet message access protocol IMAP musical instrument digital interface MIDI multipurpose Internet mail extension MIME personal identification number PIN personal unblocking key PUK subscriber identity module sim universal mobile telecommunications system UMTS World Wide Web   Web WWW, W3 short message service SMS transmission control protocol TCP