Multilingualism is the use of two or more languages, either by an individual speaker or by a community of speakers. It is believed that multilingual speakers outnumber monolingual speakers in the world's population. More than half of all Europeans claim to speak at least one other language in addition to their mother tongue. Multilingualism is becoming a social phenomenon governed by the needs of globalization and cultural openness. Owing to the ease of access to information facilitated by the Internet, individuals' exposure to multiple languages is becoming increasingly frequent, thereby promoting a need to acquire additional languages. People who speak several languages are also called polyglots.
Multilingual speakers have acquired and maintained at least one language during childhood, the so-called first language (L1). The first language (sometimes also referred to as the mother tongue) is acquired without formal education, by mechanisms heavily disputed. Children acquiring two languages in this way are called simultaneous bilinguals. Even in the case of simultaneous bilinguals, one language usually dominates the other. People who know more than one language have been reported to be more adept at language learning compared to monolinguals. Additionally, bilinguals often have important economic advantages over monolingual individuals as bilingual people are able to carry out duties that monolinguals cannot, such as interacting with customers who only speak a minority language.
Multilingualism in computing can be considered part of a continuum between internationalization and localization. Due to the status of English in computing, software development nearly always uses it (but see also Non-English-based programming languages), so almost all commercial software is initially available in an English version, and multilingual versions, if any, may be produced as alternative options based on the English original.