User blog comment:BlauesWasser/Why Zero Shouldn't be considered a cardinal/@comment-11227630-20180501052236

The cardinality of sets can be compared and sorted. The least cardinality, namely the cardinality of the empty set, is zero.

Cardinal operations contain addition, multiplication and exponentiation. Using cardinal exponentiation, $$0^0=1$$, so we can use zeros to make larger cardinals.

Some cardinals can't be made from cardinals less than it using normal cardinal operations, such as $$\aleph_0$$ and inaccessible cardinals.