== Introduction ==
[[File:Kcmetromap.png|thumbnail|right|King County Metro's frequency map in 2012. ]]
Most agencies likely publish a system or network map of their bus service. A system map can be helpful in familiarizing the customer with area coverage, but can also paint a misleading picture of actual availability when not all lines run comparable schedules. Many agencies have routes which only operate at certain times of day, such as peak period or overnight, which might appear on the system map alongside routes which run all day. A "frequent network map" includes only routes which run on a consistent and high frequency, visualizing both actual connections and the highest level of mobility on the system.