Why are social group important to the development of a cultural?

Different social groups, including ethnic groups, religious groups, and those who live in the same regions, often have their own set of beliefs or customs that their lives revolve around. When you mention "development of a cultural", I'm thinking that you meant to say "culture"? Correct me if I'm wrong on this please ^^ Often, identifying with a culture will change one's perception of the world. Perceptual, or vernacular, regions, are formed based on someone's cultural identity. Social groups will sometimes associate with certain places more than others, and/or feel uncomfortable in other places as well. In the end, everyday life is affected by the many cultures of the world. Hope this helps!

Any time if 18 but would need the money