Public transport system within the city includes both public and private sector operations. The former consist of ZUPCO buses and National Railways of Zimbabwe commuter trains. Privately owned public transport comprised licensed station wagons, nicknamed ''emergency taxis'' until 1993, when the government began to replace them with licensed buses and minibuses, referred to officially as ''commuter omnibuses''. Harare has two kinds of taxis, metered taxis and the much more ubiquitous share taxis or 'kombis'. Unlike many other cities, metered taxis generally do not drive around the city looking for passengers and instead must be called and ordered to a destination. The minibus "taxis" are the de facto day-to-day and essential form of transport for the majority of the population.