BTO released their first album under that name in the spring of 1973. Their second album was Bachman-Turner Overdrive II, and it became a massive hit in the US and their native Canada. It also yielded their best-remembered single, "Takin' Care of Business" written by Randy Bachman. BTO were one of the early hard rock bands which opted for songs backed by catchy melodies and powerful riffing. The band also promoted a strait-laced lifestyle due to the Mormon religious beliefs of Randy Bachman.

Tim Bachman left because of limited performance skills and personal lifestyle issues, and was replaced by Blair Thornton. The first album with the modified lineup, 1974's Not Fragile became a hit, including the #1 single "You Ain't Seen Nothing Yet". The band continued to steadily produce successful albums through the mid-1970s including Four Wheel Drive and Head On (both 1975).

After the release of Freeways in 1977, Randy Bachman left the group for a solo career and another band, Ironhorse. Randy was replaced by Jim Clench, formerly of April Wine, and BTO released a pair of albums before breaking up. They reunited in the 1980s, leading to a lawsuit between the brothers, as one group, led by Randy, toured as Bachman-Turner Overdrive and another, led by Robbie, toured as BTO (Robbie Bachman, Fred Turner, Blair Thornton, and Randy Murray). Interestingly enough in 1984 the line up for Bachman-Turner's first studio LP in 5 years consisted of Randy and Tim Bachman, Fred Turner and Garry Peterson on drums. In 1986 they were the opening band for the newly reformed Van Halen. By that time Fred Turner had left the band, probably to join the "other" BTO. Robbie Bachman's BTO toured and performed until December of 2004. No further plans for the band to appear are currently known, so it would be a reasonable assumption that they have retired from live performances.

From Wikipedia.