What was the automobile brand that was the beginning of General Motors?

September 16th 1908, William Durant founded the General Motors Corp. The next day he purchased Buick, then proceeded to buy other car brands. Durant was forced out in 1920 and Alfred Sloan took over GM. Sloan organized GM into a single corporation from the collection of several businesses that it had been. GM was the worlds largest auto producer from 1931-2007. Several GM brands have been closed in the past few years but Buicks continue to be produced. GM brands that were closed or sold include; Oldsmobile, Pontiac, Saturn, & Hummer. GM also has part ownership in several overseas car brands, some of which are doing very well.