In linguistics, code-switching or language alternation is the process of shifting from one linguistic code (a language or dialect) to another, depending on the social context or conversational setting. These alternations are generally intended to influence the relationship between the speakers, for example, suggesting that they may share identities based on similar linguistic histories.
Code-switching is different from plurilingualism in that plurilingualism refers to the ability of an individual to use multiple languages, while code-switching is the act of using multiple languages together. Multilinguals (speakers of more than one language) sometimes use elements of multiple languages when conversing with each other. Thus, code-switching is the use of more than one linguistic variety in a manner consistent with the syntax and phonology of each variety.