Aldermen are elected by the residents of a district. Much like congressmen, aldermen represent the people who elect them and aim to do what's in the residents' best interest. In some cases, more than one alderman can represent a district [source: Mellone]. In other countries, aldermen are more prevalent. More @Wikipedia
Hover over any link to get a description of the article. Please note that search keywords are sometimes hidden within the full article and don't appear in the description or title.