oil pencils According to Jerome McCarthy, "basic marketing" : a market is a group of potential customers with the same needs; They are willing to trade the goods or services offered by the seller in exchange for something of value, which is the way to meet the demand. Canning's view In the American society of automotive engineers standards SAEJ 687 c for automobile is defined as: power driven by itself, with a driving device, can in a fixed orbit outside the road or on regional transport passenger and cargo or vehicle traction vehicles. Cars are divided into bicycles and trains according to the overall structure. Cycling is a basic form. 4 x 2, 6 x 4, 4 x 4 and 6 x 6 are used to represent the driving characteristics. The previous number represents the total number of wheels (double tire and still count a wheel), and the latter number indicates the number of driving wheels. If all wheels are driven wheels are called all-wheel drive vehicles. The train is made up of a tractor or a bicycle trailer or semi-trailer. Car generally can be divided into the following categories, according to the use cars, buses, freight cars (commonly known as the truck), off-road vehicle, traction motor, dump truck, special vehicles, semi-trailer and special semi-trailer. In the late 19th and early 20th century, with the transition from free capitalism to monopoly capitalism, the factory itself had undergone complex and profound changes. Constantly adopt new technology to make the production rapid development; The scale of production keeps expanding, competition intensifies, and a large-scale monopoly enterprise is produced. The separation of rights and ownership and the formation of a professional management stratum; The scientific management system has been established, and a series of scientific management theories have been formed to make the enterprises mature and become modern enterprises.