Question

Is FYI (sets) { } ( empty set) considered an improper subset?​

Answer 1

The set A is a subset of the set B if and only if every element of A is also an element of B. If A is the empty set then A has no elements and so all of its elements (there are none) belong to B no matter what set B we are dealing with. That is, the empty set is a subset of every set.