The private-owned buses are quite typical of Kolkata. The private-owned buses are of two types, the regular ones and the mini-buses. The regular buses are coloured light-blue and yellow. The mini-buses are of brown and yellow colour and contain lesser number of seats. The mini-buses were started in the late seventies as a relief for the office commuters from the overloaded buses by being a sitting-only service, but this has given way to severely overloaded and crowded mini buses (and other buses too), largely due to the massive population of Kolkata.