Residential street design contributes significantly to a sense of community and the level of safety and comfort experienced by its residents.  Neighborhood streets are often seen by residents as an extension of their living space.  Most people prefer streets they can walk along and cross safely.  Traffic typically moves faster on wide streets, as drivers often wrongfully perceive that there are few dangers.  Narrowing a street with pavement markings, on-street parking, curb bulbs, or center medians can help improve safety by reducing vehicular speed, making streets easier to enter from driveways and side streets, and reducing the time and distance that pedestrians are exposed to traffic when crossing.  Typical speed reductions are 3 MPH, or 7%.  Narrowing can lessen the impact of motor vehicles on a neighborhood.