Linguistics is a large field, or set of fields, involving the scientific study of language. At the interface between the sciences and humanities, linguistics is a battleground for anthropologists, philosophers, philologists, poets, theologians, psychologists, biologists, and neurologists, all of whom seek to describe language and how it works from their own perspective. The ever-receding and highly ambitious goal is a theory of how all aspects of language work.
Linguistics has many sub-fields. This includes comparative linguistics (which compares languages to each other), historical linguistics (history of language), and applied linguistics (putting linguistic theories to practical use). As a whole, linguistics concerns itself with three major problems: how we learn languages, how languages vary, and what is universal to language. Serious progress has been made on these questions during the 20th century, but there is still much more to investigate. Language is probably the most complex form of human behavior.