GMC has quite a history, as far as automakers are concerned. As the world's second-largest, automaker, GM, which is located in Detroit, Michigan, has, and continues to be, a huge part of the automotive market. General Motors Corporation (sometimes shortened GM as well) was created in September of 1908 in Flint, Michigan. At this point, it was merely a holding company for William C. Durant's Buick brand, which also bought Oldsmobile the same year. By 1909, Durant had reigned in Elmore, Oakland (which is Pontiac today), and Cadillac, as well as other small companies. As far as truck companies are concerned, GMC bought the Rapid Motor and Reliance Motor Truck companies, both of the state of Michigan, and this led to the eventual formation of GMC Truck.
Unfortunately for Durant, he lost control of the company in 1910 because of the large debt the company had accrued under his watch (and because the market was slowing down tremendously). Durant moved on to start the Chevrolet brand a few years later, though he secretly bought enough stock to make him a controlling force in his original General Motors Company. He ended up getting the company back for a while after a large business war, and then lost control indefinitely when the years surrounding the Great Depression rolled around. Alfred Sloan picked up the slack and took control, leading GMC into a period of growth that lasted into the early 1980s.
GMC has over 260k workers spread globally, despite its headquarters being in Detroit, Michigan, U.S. It also has an amazing production capacity. In 2007, over nine million GMC trucks and cars were produced in nineteen countries. GM has a partnership with Daewoo Auto and technology collaborations with Toyota and GM. The company also has a purchasing partnership with Isuzu and Suzuki, as well as manufacturing production ventures with Suzuki, Toyota, Shaghai Industry, AvtoVaZ (Russia), UzAvtosanoa (Uzbekistan) and Renault (France). Finally, GMC also works with Fiat and Ford Motors; in fact, many of GM's collaborations are with its competitors in some shape or form. In short, the company certainly does know how to "play nice."
GMC accessories and parts are sold using the brands ACDelco and GM Goodwrench. These provide GM distributors and dealerships with parts on the global level. GM Powertrain is the brand used to market the company's engines and transmissions. GMC's biggest market is America, followed snugly by China, then Canada, the UK, and Germany. GMC also own almost half of a finance company, GMAC financial services, which aids in financing and insurance ventures. The innovative technology system OnStar, which helps owners in times of trouble and aids in directing them and answering questions, is a subsidiary of GMC.
As far as actual automobile models go, there have only been a handful of models bearing the General Motors name though Chevrolet trucks are basically the same as GMC trucks. Some models that have been introduced are: the GM EV1, which was released in the 90s, but was later discontinued, and the GM Sequel, which was a concept vehicle bearing hydrogen fuel-cell technology that appeared as a concept in 2005. However, this vehicle's name was eventually changed to Chevrolet Sequel. In addition to several other concept vehicles, the GMC Holden Statesman luxury sedan (produced from 1971 - 1985) was initially marketed as the General Motors Statesman.