The way a group lives, reflecting that group's beliefs and values. Essentially, lifestyle consists of the transient aspects of a culture or subculture. Whereas culture is usually thought of as a group's mythology and ideals, lifestyle is often thought of as the day to day aspects of a group. Examples of items covered under a lifestyle are fashion, diet, spending habits, and methods of entertainment.
When the word was first coined back in the early part of the twentieth century it was thought of as almost a dirty word which gave too much credence to consumerism and what was in vogue. Language purists would shun the word as they felt it was an insult to the english language. As time went by, however, it entered mainstream usage, as even the purists found that it was often useful to classify a group by those "superfluous" aspects, as people were already classifying others on those aspects, even before the word was ever coined.