1) Cultural regions can be defined in different ways, including formal regions that share common traits, functional regions organized around a central node, and perceptual regions that people identify with as part of their cultural identity.
2) Culture can be understood as the beliefs, institutions, language, and technology that are learned and built by a group of people. Key elements of culture include cultural traits, complexes, and realms of different scales.
3) Material culture refers to the physical objects and spaces that define a culture, while non-material culture includes ideas, beliefs, values, and language. Both aspects shape a group's behaviors and perceptions.