Relation between an object, called an element, and a given set.
Symbols
The symbol “∈” is read as: “is an element of” or “belongs to”.
The symbol “∉” is read as: “is not an element of” or “does not belong to”.
Example
Consider the set E = {0, 1, 2, 3, 4, 5, 6}.
The number 5 is an element in set E so we write: 5 ∈ E.
The number 8 is not an element in set E so we write: 8 ∉ E.