MCI Communications was a major telecommunications company in the United States, known for providing long-distance telephone services. Founded in 1963, it played a significant role in the telecommunications industry, especially during the deregulation of the market in the 1980s. MCI was recognized for its innovative services and competitive pricing, which challenged the dominance of AT&T. In 1997, MCI Communications merged with WorldCom, creating one of the largest telecommunications companies in the world. However, the company faced significant challenges in the early 2000s, including a major accounting scandal that led to bankruptcy. Despite these issues, MCI's legacy remains influential in the evolution of modern telecommunications.