Language at its most basic is talking, reading and writing. The study of language is called linguistics. Humans have the most complicated languages on Earth. Although almost all animals communicate, human language is unique. Its use of syntax, and its huge learnt vocabulary are its main features. There are over 7,300 languages spoken around the world. The world's most spoken first language is Mandarin Chinese, and the most spoken language is English. This includes speakers of English as a second language.