Identified through Language

Without language, society as a whole and smaller divisions of culture wouldn't have developed into unique and individual identities. Communication helps people develop and relate to others, so it also helps them form their personal cultures within the subdivisions of our civilization. Language is an important tool to use to dig into a certain culture; if you know the language, you can begin to fully immerse yourself in the culture.
Take English for example. American English and British English are two completely different languages, in terms of spelling of certain words, slang and other terminology. Within English are many subdivisions as well, with slang and different terminology being used within different geographical regions. You can identify a person from the south by their language, they might use the word "coke" for soda, so when you hand them a coca-cola they actually wanted a sprite.
Language can also identify the most inner-workings of individual human beings. The way people phrase things, state their opinions and express their feelings reveals a lot about them as a person. Someone who criticizes others with harsh words may not feel very well about themselves. Others who use a sophisticated tongue may be especially educated or feel the need to fake intelligence. Overall, the language people use helps them define who they are. And who they are helps determine their language, in an ongoing cycle. Language is pliable, it can evolve to match the changes of the individual, it can reshape and reform itself. Language helps people define themselves, and it helps society develop into a variation of culture and unique individual components.