Code-switching is a communicative behavior where two or more speakers use words and phrases from different languages while conversing. This phenomenon can lead to language change, even the creation of new languages. Examples include Spanglish (a mix of Spanish and English), Hinglish (Hindi and English), and Taglish (Tagalog and English). Code-switching is not simply mixing two languages but rather using words, phrases, grammar, and other cultural elements from different languages to communicate more fully. It often occurs in multilingual communities where speakers have knowledge of multiple languages or dialects. AI researchers need to consider code-switching when building language models as it can significantly impact the accuracy of speech recognition systems.