Set Cardinality

Cardinality of a set is the size of a set.

For finite sets, the cardinality of a set is the concrete number of elements in a set.

Cardinality of a set $S$ is denoted by $|S|$, occasionally equated to $n$: $|S| = n$

An infinite set has infinitely many elements, thereby an infinite cardinality

a finite set, e.g. $\{1,2,3, \dots,100\}$ has finite cardinality (here the element after elipses is called terminal set member.

Definition: The cardinality of S, denoted |S|, is the number of elements in S.