Some industries and areas of interest can be called "worlds". Each different "world" is not only a type of business, but also a way of life

For example, "the Art world" means artists, art buyers, art gallery owners, museums, art magazine editors, and so on. It also includes their parties, their topics of conversation, the types of places that they live, and so on.

Other examples of "worlds" based on industries or interests are:

the business world

the academic world

the drug world

the online world

the financial world

the gaming world