1 The weight of a fire fighter would be an example of a continuous variable; since a fire fighter's weight could take on any value between 150 and 250 pounds.  Suppose we flip a coin and count the number of heads. The number of heads could be any integer value between 0 and plus infinity.
A postal code is a series of letters and/or digits appended to a postal address for the purpose of sorting mail. Once postal codes were introduced, other applications became possible. In February 2005, 117 of the 190 member countries of the Universal Postal Union had postal code systems.
The ZIP code is the system of postal codes used by the United States Postal Service (USPS). The letters ZIP is an acronym for Zone Improvement Plan,. The letters are written properly in capital letters. The word ZIP was chosen to suggest that the mail travels more efficiently, and more quickly, when senders use it.