A school bus is any type of bus owned, leased, contracted to, or operated by a school or school district. It is regularly used to transport students to and from school or school-related activities, but not including a charter bus or transit bus. Various configurations of school buses are used worldwide; the most iconic examples are the yellow school buses of the United States which are also found in other parts of the world. In North America, school buses are purpose-built vehicles distinguished from other types of buses by design characteristics mandated by federal and state/provincial regulations. In addition to their distinct paint color (National School Bus Glossy Yellow), school buses are fitted with exterior warning lights (to give them traffic priority) and multiple safety devices. Kid hack In the second half of the 19th century, many rural areas of the United States and Canada were served by one-room schools. For those students who lived beyond practical walking distance from school, transportation was facilitated in the form of the kid hack; at the time, "hack" was a term referring to certain types of horse-drawn carriages. Essentially re-purposed farm wagons, kid hacks were open to the elements, with little to no weather protection. In 1892, Indiana-based Wayne Works (later Wayne Corporation) produced its first "school car" A purpose-built design, the school car was constructed with perimeter-mounted wooden bench seats and a roof (the sides remained open). As a horse-drawn wagon, the school car was fitted with a rear entrance door (intended to avoid startling the horses while loading or unloading passengers); over a century later, the design remains in use (as an emergency exit). In 1869, Massachusetts became the first state to add transportation to public education; by 1900, 16 other states would transport students to school. Following the first decade of the 20th century, several developments would affect the design of the school bus and student transport.