Harley-Davidson, also known as HD, has been around for over 100 years, beginning in 1903 in Milwaukee, Wisconsin between two friends. Though William and Walter Davidson, Arthur Davidson's brothers, would join the project, the original prototype was conceived by William Harley and Arthur Davidson. Together, their working relationship founded the HD Company, later this company would grow enough to deserve to be incorporated, with the help of Walter's skills as a mechanic and William Davidson's abilities to make tools.

During 1903 Harley-Davidson turned out a grand total of 3 motorcycles, all were bought and paid for before completion. Gray was the standard color of the first motorcycles, which were often referred to as the ?Silent Gray Fellows?. By 1905, the Company had grown at such a rate that they were now selling motorcycle motors, marine motors, reversible propellers, and float feed carburetors along with the standard motorcycles.

The Harley-Davidson company only continued to prosper through the next decade. Among the biggest fans of the company was the United States Postal service, who in 1914 used 4,800 of the company's bikes but nine departments in total used the company's products in the federal government in that year. By 1916, the military was in on the act and they began outfitting their HD's with machine guns in skirmishes with Panch Villa. The federal government did not ease up on their use of HD during the first World War, on the contrary, the government purchased fifty percent of all of the HD motorcycles during this period and shipped them overseas for the military to use.

The sport of racing was the way that HD thrived and prospered in the post-war years of the 1920s. Unlike many companies during the 1930s, the effects of the Great Depression were not strong enough to press Harley-Davidson out of business, they continued to prosper. Repeating their government service in the 1940s, the HD bikes were a valuable tool during the Second World War.

In the decade of the 1950s, the company began employing more aggressive marketing strategies and saw increased growth. Once again war broke out, this time in Korea but unfortunately motorcycles were replaced in popularity with the military with the Jeep. Harley-Davidson was free to concentrate on its civilian consumers.

The 1960s were a decade of change for the company, as well as the rest of the United States. Change can be seen through the company's decision to produce the 3-wheeled golfing cart. By the end of the decade these carts cornered about one third of the United States market, and were even used oversees. In according to the change theme, motorcycle accessories became part of the Harley-Davidson family during the 1960s too.

Racing once again became a focus during the 1970s, as Harley-Davidson motorcycles received advances in technology that allowed them to make great strides in the sport. The 1980s were a decade of great financial change for many companies, and for the HD Company, this was especially true when they became a private ownership again as the result of a buyback. The company seemed to show a renewed interest in building better machines so much so that they won the contract with the California Highway Patrol in 1984, 1985, 1987, 1988 and 1989.

Customized factory motorcycles took center stage during the 1990s, when Harley-Davidson introduced the FLSTF Fat Boy. The goal of the new bike was to invoke the feel of past bikes while keeping up to date. The Twenty first century has come and the company remains strong. The basic line of the company is composed of the Sporster, the Dyna, the Softail, the VRSC, and a Touring line, each line then diverges into different models.