Irrespective of whether it's a public or private bus, they all have the same functionality i.e. to transport people on fixed schedules. First, buses are built on demand by the manufacturer from the ground up. The entire vehicle has 2 major components: the chassis and body. There are 3 types of manufacturers, some will only build the chassis. Others will focus on constructing the body. whereas the big manufacturers will build the chassis and the body together in-house. Some of the top manufacturers in the industry are Ford and Chevrolet. Other brands include Blue Bird, Turtle Top and Goshen. There are still others like Startrans, Starcraft and more. Once the vehicle is ready, its sold and delivered to the buyer at wholesale prices. They can either be a private dealership or a local public transportation department. The private dealer will sell the bus at a higher price to individual buyers. Thus making thousands of dollars in profit. Whereas the public transportation department will hire a driver to operate the bus. They will even train the driver for a few weeks on how to operate the bus. Because chances are that the driver was before operating a bus built by a different manufacturer and its functionality was completely different. The public transportation department ensures that wherever there is a road, its buses will be operating on them at least once in a day. The frequency of operations depends on the demand. The department creates a map of all the roads under its jurisdiction. On every road, it constructs and maintains several bus stops. Depending on the budget, the bus stops can either be fully constructed bus stations or just a pole with a metallic board, suggesting its a bus stop and will include all the bus numbers that will halt near its position. Every driver is expected to run his bus on dedicated roads, halt at every stop, pickup and drop off passengers and finally return back to the hub of the transportation department. The journey starts from this hub and ends at it. In simple terms, every bus is stationed at the transportation hub, the driver will report to work every day at the hub, he will be given a fixed route to operate his bus, he will get inside the vehicle, turn it on, drive out of the huge gates of the hub and move in the direction of the route he has been assigned. Once he is on the assigned route, he will keep riding until he finds a public bus stop. The vehicle is always empty when the driver drives it out of the hub. There will be no passengers to drop at the first stop, people will be entering but not getting off it. From the second stop onward, people will be stepping in and out at every halt. All the passengers will step out at the last stop. From there, the driver will take the bus back to the hub empty. The vehicle and the driver will rest for a few hours until they both get ready for the next route. Continue reading: https://www.quora.com/How-do-the-buses-work/answer/Charles-Kaufman-8