In modern mathematics set theory, an element is every object that makes up a set, and a set is made up of elements, and every object that makes up a set is called an element that makes up a set. Set is one of the basic concepts in mathematics. The totality of things with certain attributes is called "set", and elements are everything that constitutes a set. The branch of mathematics that studies the operation and properties of sets is called set theory or set theory. The definition of set is very broad, not limited to mathematics, but also widely used in production and life. All things with specific attributes that make up a specific set can be called elements, so the definition of elements is also very broad. Some specified objects are grouped together into a set, and each object is called an element.