Language is a species-specific trait of human beings.
As far as we know, our ability to speak a language distinguishes us from all other animal species. While children learn a language, much of our linguistic knowledge seems to be innate, an intrinsic part of our mental framework. By the time children begin school, they have already learned the majority of rules governing their native language and can produce virtually all kinds of sentences that it permits. A person's ability to use language is determined early in life. When we learn a language, we are acquiring a vast system of mostly subconscious rules that allow us to make meaningful and increasingly complex utterances.