How did Robert l Johnson make his money?

Robert L. Johnson made his money primarily through the founding of BET (Black Entertainment Television) in 1980, which became the first cable network aimed at African American audiences. He grew the network into a successful media company, eventually selling it to Viacom in 2001 for $3 billion. Additionally, Johnson has invested in various business ventures, including real estate and sports teams, further contributing to his wealth. He is also known for being the first African American billionaire in the United States.