Informal transit systems are transit modes that are not planned citywide by a municipal authority, but rather are private systems that spring up to meet demand.
They are demand-driven, often unscheduled and flexible public transport services provided by small operators, in small to medium-size motorized or non-motorized vehicles, generally without effective regulatory frameworks.
They are often characterized by:
- Unorganized (individual or small) owner-operators
- Smaller-size vehicles (mini-buses, share-taxis, or share-autos)
- Flexible schedules, with higher frequencies during peak periods
- Fixed-route services with flexible curbside pick-up and drop-off
- Some level of regulation by local authorities, although many are completely unregulated