The multiplicity of languages is a major dividing factor in world society, reinforcing geographical, socio-economic (especially caste or class), political, ideological, professional and religious separatism. It prevents or hinders communication and the spread of education, and therefore aggravates international misunderstanding and mutual suspicion. Multilingualism within a country results in poor communications between members of different language communities and between those communities and the government. It can lead not only to mistrust and to political tension, but also to poor levels of literacy and problems in the judiciary when different languages may be used and transcripts required in order for a case to be heard at all.
Language barriers impede international communication in general and individuals in particular by rendering them unable to speak and correspond with whomever they wish, or read the periodicals and books they want to read. Bilingualism enables people to participate fully and directly in world culture and universal dialogue; monolingualism leaves the individual with a more parochial, and fearful, worldview.
Different languages arose because of lack of contact between people of different regions, but especially because societies with distinct economic, moral and cultural traditions required specific vocabularies and linguistic structures. But at the same time, even within communities, distinctions between social groups—especially between a dominant elite and the mass of the population—came to be reflected in differences in idiom and vocabulary, in the meaning given to certain words, as well as in pronunciation. Millions of people today speak languages that are not understood by neighbouring groups, even though close economic and social links have been established and populations have intermingled. Thus, paradoxically, the very richness and diversity of languages can render communication difficult, just as its elaboration can perpetuate privilege.
The exact number of languages is not known because of difficulty in agreeing upon the distinction between a language and a dialect. The figure of 2,700 to 3,000 languages is frequently encountered. Of these approximately 150 (60 in developed and 90 in developing countries) have more than one million speakers. In Africa, for example, with approximately half the population of Europe, over 1,000 languages are spoken as against the 60 in Europe. In effect the average African language is spoken by less than 200,000 people. At the other extreme, languages such as English, French, Spanish, Arabic, Portuguese and German are each spoken internationally by a total each of from 100 to 350 million persons. Mandarin Chinese is spoken by some 650 million people internationally. Russian, Hindi, Bengali and Japanese languages have limited use outside their motherlands and thus their 660 million speakers do not have the advantage of belonging to an international linguistic community. On the other hand, the USSR and India each has a considerable number of languages spoken internally, which in India's case at least has caused a great deal of friction. Both India and Japan frequently resort to English for international communication, while Russia turns to French.