In modern mathematics set theory, an element refers to every object that constitutes a set. In other words, a set consists of elements, and every object that constitutes a set is called an element that constitutes a set. For example, 1, 2,3 in the set {1} is an element in the set.
The branch of mathematics that studies set operations and their properties 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 to form a set, where each object is called an element.
The elements in the set are equal, and there is no order. So to judge whether two sets are the same, we only need to compare whether their elements are the same, without considering whether the arrangement order is the same.