Book: The Five-Minute Linguist
Chapter: 2. You're a Linguist? How Many Languages do You Speak?
Blurb:
People who speak multiple languages are called ‘polyglots’. Many linguists work on describing particular languages. Some linguists work at the more abstract level of linguistic theory, while others study speech or historical linguistics. Psycholinguistics, neurolinguistics, sociolinguistics are other disciplines that explore what language is about.