Deputy mayor is an elective or appointive office of the second-ranking official in many local governments.
Duties and functions
Many elected vice mayors are members of the city council who are given the title and serve as acting mayor in the mayor's absence. Appointive deputy mayors serve at the pleasure of the mayor and may function as chief operating officers.
There may be within the same municipal government where a deputy mayor(s) appointed by the mayor to policy areas and a popularly-elected vice mayor who serves as the mayor's successor in the event the office is vacated by death, resignation, disability, or impeachment.
In other cities the vice mayor presides over the city council, and may not vote except to break ties. Like the deputy mayor in other systems, the popularly-elected vice mayor becomes acting mayor in the mayor's absence. As previously noted, in some few cities, this office is elected separately and does not entail the elevation by the council of one of its members to be speaker. In some U.S. cities, the mayor and deputy or vice mayor run together as a ticket similar to how president and vice president run at the national level.
New York City, USA
Davao City, Philippines
In Davao City, there is both an elected vice-mayor as a direct constitutionally-mandated deputy of the Mayor of Davao City and appointed deputy mayors. The deputy mayors are appointed to administer each ethnic minorities situated in Davao City.