Secret Service code name

The United States Secret Service uses code names for U.S. presidents, first ladies, and other prominent persons and locations. The use of such names was originally for security purposes and dates to a time when sensitive electronic communications were not routinely encrypted; today, the names simply serve for purposes of brevity, clarity, and tradition. The Secret Service does not choose these names, however. The White House Communications Agency maintains a list that candidates choose from, often choosing ones that resonate with them personally.
According to an established protocol, good codewords are unambiguous words that can be easily pronounced and readily understood by those who transmit and receive voice messages by radio or telephone regardless of their native language. Traditionally, all family members' code names start with the same letter.
The codenames change over time for security purposes, but are often publicly known. For security, codenames are generally picked from a list of such 'good' words, but avoiding the use of common words which could likely be intended to mean their normal definitions.
Political candidates and their spouses.
U.S. Secret Service codenames are often given to high-profile political candidates (such as presidential and vice presidential candidates), and their respective families and spouses who are assigned U.S. Secret Service protection. These codenames often differ from those held if they are elected or those from prior periods if they held positions needing codenames.
Locations, objects, and places.
U.S. Secret Service codenames are not only given to people; they are often given to places, locations and even objects, such as aircraft like Air Force One, and vehicles such as the Presidential State Car.
In fiction.
In popular culture, the practice of assigning codenames is often used to provide additional verisimilitude in fictional works about the executive branch, or high-ranking governmental figures.