Animals do not have language. Language is a system of arbitrary vocal symbols used for human communication. Language is human-specific. All human languages have certain characteristics in common and linguists have identified these characteristics as defining features of human language. These features, now called design features, are found utterly lacking in animal communication and thus set human language apart from animal cry systems. The following five design features of human language have been identified by the eminent American linguist Hockett: arbitrariness, duality, productivity, displacement and cultural transmission. Human language is arbitrary. This refers to the fact that there is no logical or intrinsic connection between a particular sound and the meaning it is associated with. There is no reason, for example, why English should use the sounds /dɒg/ to refer to the animal dog, or why Chinese should use “gou” to refer to the same animal. The relationship between the sounds and their meaning is quite accidental. By duality is meant the property of having two levels of structures, such that units of the primary level are composed of elements of the secondary level and each of the two levels has its own principles of organization. Productivity refers to man’s linguistic ability which enables him to produce and understand an infinitely large number of sentences in our native language, including the sentences which were never heard before. This feature equips human beings with the ability to produce completely new utterances and ideas. There is no productivity to speak of in animals’ cries. Displacement is a property of language enabling people to talk about things remote either in space or in time. Most animals can only communicate about things in the immediate situation, but human beings can communicate about things that are absent as easily as about things that are present. Besides, language is culturally transmitted. It cannot be transmitted through heredity. A human being brought up in isolation simply doesn’t acquire language, as is demonstrated by the studies of children brought up by animals without human contact. Animals transmit their cries through heredity, that is, simply from parent to child. The above features are adequate to show that human language is sharply distinguished from animal communication systems.