The symbol ‘∈’ represents “belongs to”
For example, if B = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10} and A = {2, 4, 6, 8, 10}
Then we can say B is a set of all-natural numbers and A is a set of even numbers,
i.e., B ∈ N and A ∈ E
Where N represents natural numbers and E represents even numbers.