Language is a unique system which created for the purpose of communication. All creatures are capable of communicating with other members of their species; nevertheless there are some properties of language that are only present in humans. They are reflexivity, displacement, arbitrariness, productivity, cultural transmission and duality.
Reflexivity:
Reflexivity is a special property of human language that allows language to be used to think and talk about language itself.
Displacement:
Displacement is a property of language that allows users to talk about things and events not in present in the immediate environment.
Arbitrariness:
Arbitrariness is a property of language describing the fact that there is no natural connection between a linguistic form and its meaning.
Productivity:
A property of language that allows users to create new expressions is called productivity. It is also called as “creativity” or “open-endedness”.
Cultural Transmission:
The process whereby knowledge of a language is passed from one generation to the next is known as the cultural transmission.
Duality:
Duality is a property of language whereby linguistic forms have two simultaneous levels of sound production and meaning, also called “double articulation”. The two levels are meaningless elements; i.e., a limited inventory of sounds or phonemes like b, i and n. Another level is made up of meaningful elements; i.e., a virtually limitless inventory of words or morphemes likes ‘bin’ and ‘nib’ which are distinct meanings.
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