Language development is the process through which a person develops and learns a language throughout infancy and childhood, which typically refers to a person’s first or primary language. There are a number of theories with regard to how people learn and develop language, and each theory takes different approaches to language acquisition. The development of language tends to occur over the first 10 years or so of a person’s life, and there are different aspects of language that develop at different times. Language development is often an area of research and investigation undertaken by linguists, though it is difficult to prove any one theory conclusively due to the nature of this process.
Since someone does not have language to describe the process of language development as it occurs, there is little firsthand evidence to how the process happens. Most theories and understanding of the process come from observation and research with regard to different developmental stages of infants and children. There are four major theories regarding language development, and each one takes a slightly different approach to the process.
One of the earliest language development theories is that it occurs due to operant conditioning. This theory has typically been supported by behaviorists such as B.F. Skinner. Noam Chomsky’s theory of development through a language acquisition device (LAD) that is unique to the human race is among the most strongly supported and heavily influential theories on the subject.
There are also theories that view language acquisition through a similar approach to Chomsky, but without the inclusion of the LAD within the cognitive facilities of a human being. The final major theory on language development is something of a combination of the others. It indicates that people detect patterns in language as infants, and that social interaction through childhood pushes people into further development of language.
Language development tends to occur over the first decade or so of a person’s life, and Chomsky’s theory also indicates that once a certain point is passed without developing language, a person simply loses the ability to properly do so. There are also different aspects of language that people develop, including grammar, which are the rules that govern how words and markers in a particular language are ordered when expressed. Phonology, which deals with the sounds used to make up a language, is also important to the proper development of language. Throughout language development a person learns these various rules and sounds and eliminates other options that are not used in his or her language to communicate with others.