• Linguistics -- the study of language and languages.
• Comparative linguistics -- the study of the history and evolution of languages.
• Psycholinguistics -- study of language from a cognitive and developmental view.
• Sociolinguistics -- the study of language as it pertains to social classes, ethnic groups, genders...

• Phonetics -- the study of phonemes.
• Phonemes -- the sounds of a language.
• Syntax -- the grammar of a language.
• Morphology -- the study of morphemes -- usually seen as a part of syntax.
• Morphemes -- word stems and affixes, i.e. units of meaning in a language.
• Semantics -- the study of the meaning of language.
• Lexicology -- the study of words -- a part of semantics.

The Top Twelve Languages

These languages have over 100 million each, inc. non-native speakers -- although the actual numbers are difficult to estimate!  If you knew all 12 of these, you could probably communicate with more than 2/3 of the world!

• 1st/2nd (tie):
• Mandarin Chinese (Putonghua) -- 1 billion
• English -- 1 billion (the world's most popular second language)
• 3rd:  Hindu-Urdu (two dialects, each with a different alphabet) -- 900 million.
• 4th:  Spanish -- 450 million.
• 5th:  Russian -- 320 million.
• 6th/7th (tie):
• Arabic -- 250 million.
• Bengali -- 250 million.
• 8th:  Portuguese -- 200 million.
• 9th:  Malay-Indonesian (two dialects) -- 160 million.
• 10th:  Japanese -- 130 million.
• 11th/12th (tie):
• French -- 125 million
• German -- 125 million

There are a number of ways of classifying the thousands of languages of our world.  What follows is based on Greenberg's system, a recent classification which is still controversial.  If you would like to see maps of these families, click here.  Some of the larger examples of each category have an estimated population in brackets; a second number indicates an estimate of non-native speakers.

• Khoisan (Old languages of Southern Africa, e.g. Bushmen)
• Niger-Congo (e.g. Swahili [5-60], Yoruba [20], Fula [13], Zulu [6])
• Nilo-Saharan (North Central Africa)
• Afro-Asiatic (inc. Ancient Egyptian)
• Semitic (e.g. Arabic [180-250], Hebrew [4])
• Berber
• Cushitic
• Omotic
• Chadic (e.g. Hausa [25])
• Indo-European -- a very well studied family.
  
• Germanic (e.g. English [427-1000+], German [121-125]), Dutch [21])
• Romantic (e.g. French [116-125], Italian [65-70], Spanish [266-450],  Portuguese [165-200])
• Celtic (e.g. Gaelic, Welsh, Breton)
• Slavic (e.g. Russian [158-320], Ukrainian-Belarus [60], Polish [42])
• Baltic [4] (e.g. Lithuanian, Lettish)
• Greek  [11]
• Albanian [6]
• Armenian [6]
• Indo-Iranian (e.g. Urdu-Hindi [223-900], Bengali [162-250], Panjabi [60-85], Marathi [80], Bhojpuri-Maithili [65], Persian [22])
• Basque (Spain-France border [1])
• Caucasian (in the Caucasus Mountains of Russia, e.g. Georgian [4]) -- speculative:  most consider at very least that Georgian (Kartvelian) is separate from the other Caucasian languages.
  
• Uralic (e.g. Finnish [5], Hungarian [11], Lapp) -- a very well studied family.
  
• Altaic (e.g. Turkish [50-70], Azerbaijani [14], Uzbek [15], Mongolian [4]) -- some consider Korean and Japanese part of this family.
  
• Korean [66-75]
• Japanese [124-130]
• Dravidian (southern India, e.g. Tamil [50-65], Telugu [50-70], Kannada [26], Malayalam [26])
• Sino-Tibetan (e.g. “Chinese” or Mandarin [720-1000], Wu [77-85], Cantonese [46-70], Burmese [22])
• Austric -- a highly speculative grouping; most linguists consider these independent.
  
• Miao (Southern China)
• Austroasiatic (e.g. Vietnamese [55-75], Cambodian [7])
• Daic (e.g. Thai [20], etc.)
• Austronesian (e.g. Indonesian/Malay [17-160],  Javanese [75-80], Pilipino [40], Polynesian languages such as Maori and Hawaiian) -- a very well studied family.
  
• Indo-Pacific (about 700 Papua-New Guinea languages) -- very speculative; we don't even have very complete information on most of these languages!
  
• Australian (170 Aborigine languages)
• Paleosiberian (far Northeastern Siberia, near the Bering Strait)
• Eskimo-Aleut (from Alaskan islands, across northern Canada, to Greenland)
• Na-Dene (Northwest Pacific coast Indians, plus Navaho and Apache)
• Amerindian (600 languages of North and South America) -- the most speculative of all; most specialists in American Indian languages consider these to be independent families.
  
• Macro-Algonquin family (e.g. Cree, Ojibwa)
• Macro-Souian family (e.g. Sioux, Iroquois)
• Hokan family (California, Mexico; sometimes classified with Macro-Souian)
• Penutian family (California, Oregon, Mexico, Central America; e.g. Mayan)
• Aztec-Tanoan family (e.g. Nahuatl [1], Comanche, Hopi; sometimes classified with Penutian)
• Oto-Manguean (Mexico, Central America; sometimes grouped with Aztec-Tanoan as Central Amerind)
• Andean-Equatorial family (e.g. Quechua [7], Guarani [3]; includes Macro-Tucanoan)
• Chibchan family (South America; includes Paezan)
• Gé-Pano-Carib family (South America)