A shuttle bus is a bus which travels a short route, and is usually free to ride. A classic shuttle bus simply runs back and forth between two points, although others may make several stops to pick up passengers along the way. Shuttle buses are used to fill gaps in public transit, as a complimentary service for people such as hotel guests, as a public safety initiative, and as a method of controlling traffic and keeping large groups of people organized. They may be run by public transit agencies or private companies.
A classic example of a shuttle bus is an airport shuttle which travels to airport hotels to pick up passengers, carries passengers from remote parking lots to the airport terminals, or shuffles passengers between the terminals of a large airport. This type of shuttle bus allows people to drive to a location near the airport, park, and take a shuttle to the terminal they need to reach, and it can also be used to connect people to rental car services or public transit. Airport shuttles may be run by hotels, public transit agencies, or the airport itself.
Colleges, universities, and companies with large campuses may also use shuttle bus services to get people where they need to go. A campus may be closed to traffic, but very large, making a shuttle bus critical for people who need to get from one end to another, and shuttle buses can also be used to manage parking problems, and get students from dorms or public transit to their classes. Campus shuttle buses can also be beneficial for public safety, as they reduce the number of students walking around campus after dark, and some schools may include shuttles to local hangouts for public safety reasons as well.
Large events may also hire shuttle buses to manage attendees. Since event locations may lack parking or close public transit connections, organizers can use shuttle buses to get people to and from the event. This can also be used to encourage people to consider taking public transit to an event, with the assurance that they will have a ride on a shuttle bus. Public transit agencies may run shuttle buses between parking lots and train stations, ferries, and other public transit stations for much the same reason; by getting people to take public transit into congested areas, public transit agencies can reduce overall traffic and congestion.