Among the invented languages that people actually speak is Klingon, which came from a television series, Star Trek. Today television is inventing more languages.
As Amy Chozick notes in the NY Times, “Game of Thrones” needed the feeling of authenticity that language (and subtitles) can impart.
She writes, “At his best friend’s wedding reception on the California coast, David J. Peterson stood to deliver his toast as best man. He held his Champagne glass high and shouted ‘Hajas!’ The 50 guests raised their glasses and chanted ‘Hajas!’ in unison.
“The word, which means ‘be strong’ and is pronounced ‘hah-DZHAS,’ has great significance for Mr. Peterson. He invented it, along with 3,250 other words (and counting), in the language he created for the HBO fantasy series ‘Game of Thrones,’ called Dothraki”