Definition:Countable Set

Also known as
The words denumerable and enumerable are sometimes encountered. They may mean the same thing as countable, or they may mean countably infinite.

Some sources use countable to mean countably infinite.

However, this usage seems to be going out of fashion, as the very concept of the term countable implies that a set can be counted, which, plainly, a finite set can be.

Also see

 * Equivalence of Countable Set Definitions
 * Surjection from Natural Numbers iff Countable


 * Definition:Finite Set
 * Definition:Infinite Set
 * Definition:Uncountable Set


 * Sufficient Conditions for Uncountability