The American Basketball Association (ABA) was a professional basketball

Basketball

Basketball is a team sport in which two teams of five players try to score points by throwing or "shooting" a ball through the top of a basketball hoop while following a set of rules...

 league founded in 1967. The ABA ceased to exist with the ABA–NBA merger in 1976.
The original ABA was founded in 1967, competing with the well-established National Basketball Association

National Basketball Association

The National Basketball Association is the pre-eminent men's professional basketball league in North America. It consists of thirty franchised member clubs, of which twenty-nine are located in the United States and one in Canada...

, until the ABA–NBA merger in 1976. According to The NBA Encyclopedia, its long-term goal was to force a merger with the more established league.