Is there such thing as set of empty set?

While I'm reading Is an empty set equal to another empty set?, I wonder if {∅} = ∅?

And it leads to my doubts : is there such things as "set of empty set" with notation {∅}?

If so, then {∅} = ∅?

$\{\emptyset \}$ has one element, while $\emptyset$ has $0$ elements.