Cultural diversity is the quality of diverse or different cultures, as opposed to monoculture, as in the global monoculture, or a homogenization of cultures, akin to cultural decay. For example, before Hawaii was conquered by Europeans, the culturally diverse Hawaiian culture existed in the world, and contributed to the world's cultural diversity. Now Hawaii has been westernized; the vast majority of its culture has been replaced with Western or American culture. The phrase cultural diversity can also refer to having different cultures respect each other's differences.^{[citation needed]} The phrase cultural diversity is sometime misused to mean the variety of human societies or cultures in a specific region, or in the world as a whole; but these phenomenon are multiculturalism rather than cultural diversity. The culturally destructive action of globalization is often said to have a negative effect on the world's cultural diversity.

The many separate societies that emerged around the globe differed markedly from each other, and many of these differences persist to this day. As well as the more obvious cultural differences that exist between people, such as language, dress and traditions, there are also significant variations in the way societies organize themselves, in their shared conception of morality, and in the ways they interact with their environment. Cultural diversity can be seen as analogous to biodiversity.