Until the 1600s, English was, for the most part, spoken only in England. However, during the course of the next two centuries, English began to spread around the globe as a result of exploration, trade, colonization, and missionary work. English gradually became the primary language of international business, banking, and diplomacy. Currently, more than 80 percent of the information stored on computer systems worldwide is in English. Two thirds of the world’s science writing is in English, and English is the main language of technology, advertising, media, international airports, and air traffic controllers. Today there are more than 700 million English users in the world, and over half of these are non-native speakers, constituting the largest number of non-native users of any language in the world.