The next should include the street address, city address, state address, and then the ZIP code lookup. The ZIP code is the most important element of the addresses. It is because the ZIP codes help the Postal Office to sort the mails as they direct them to the relevant destinations. The ZIP code lookup format was introduced in 1963 and then it included five numbers. Later in 1983 ZIP code, systems now had five plus four-digit format. The new ZIP code system had a hyphen after the five digits and four more numbers. It was to ensure that it easily determines the exact location.