In mathematics, it is a common practice to index or label a collection of objects by some set I called an index set. The indexed collection is called a family and normally denote by (A_i)_i∈I. Mathematics is the study of quantity, structure, space and change. ... The notion of a set is one of the most important and fundamental concepts in modern mathematics. ... In mathematics, an index set is another name for a function domain. ...

See also index (mathematics) and family (mathematics) In mathematics, an index is a superscript or subscript to a symbol. ... In mathematics, an index set is another name for a function domain. ...