adopted in 2002; it began using the initialism as its trading name in 2011. The previous name of World Wrestling Federation (WWF), used since 1979, was changed after a court case brought by the World Wildlife Fund (WWF), which is now called the World Wide Fund for Nature. X Xerox – named from xerography, a word derived from the Greek xeros (dry) and graphos (writing). The company was founded as The Haloid Company in 1906, launched its first XeroX copier in 1949, and changed its name to Haloid Xerox in 1958. Xiaomi – Xiaomi is the Chinese word for "millet". XIX Entertainment – XIX is 19 in Roman numerals, so the company is named indirectly after Paul Hardcastle's single 19, and directly derived from 19 Entertainment – see above. Xstrata – name for a Swiss global mining and extraction company, formerly known as Sudelektra. The name is derived from the terms "extraction" and "strata" (sedimentary levels). The name was created in 1999 by John Lloyd of the design consultancy, Lloyd Northover. XTO Energy – founded in 1986 as Cross Timbers Oil Company, it went public under the stock ticker XTO, and changed its name to XTO Energy Inc in 2001. It is now owned by ExxonMobil. Y Yahoo! – word Yahoo was invented by Jonathan Swift and used in his book Gulliver's Travels. It represents a person who is repulsive in appearance and barely human. Yahoo! founders David Filo and Jerry Yang jokingly considered themselves yahoos. It's also an interjection sometimes associated with United States Southerners' and Westerners' expression of joy, as alluded to in Yahoo.com commercials that end with someone singing the word "yahoo". It is also sometime jokingly referred to by its backronym, Yet Another Hierarchical Officious Oracle. Yakult – official claims state that the name is derived from jahurto, an older form of jogurto, the Esperanto word for "yogurt". However, it has also been claimed that the name is derived from the fact that the product was developed from ancient Mongolian practices of culturing yak's milk in a sack made from a yak's stomach – the combination of Yak and Culture in English giving the product name as "Yakult". Yamaha – after Torakusu Yamaha, who founded the company as Nippon Gakki Seizō Kabushiki Gaisha (Japan Musical Instrument Manufacturing Corporation) in 1897 after repairing a reed organ. The name was changed to Yamaha Corporation on 1 October 1987.