The term 'class' can refer to a variety of different concepts. For example, a PERIOD is a set amount of time in which a lesson or activity takes place. A LINE is a group of people or things arranged in a straight row. A FILE is a collection of documents or records kept together. KIND refers to a TYPE or CATEGORY of something. An ACT is a deed or performance. ILK is a TYPE or KIND of person or thing. SORT is a TYPE or KIND of person or thing. TIER is a level or rank in a hierarchy. TYPE is a CATEGORY or class of something. Year is a PERIOD of twelve months. CASTE is a social class or division based on wealth, inherited rank, or occupation. CLOWN is a comic entertainer who wears an outlandish costume and makeup. GENRE is a CATEGORY of artistic composition, as in music or literature. GENUS is a taxonomic CATEGORY ranking below a family and above a species. GRADE is a degree or level of quality, rank, or importance. ORDER is a group of people or things of the same KIND. STYLE is a particular KIND, SORT, or TYPE. CATEGORY is a general group of people or things. ELEGANCE is the quality of being graceful and stylish in appearance or manner.