Short answers, pulled from the story.
Contemporary R&B is a popular music genre that originated from African-American musicians in the 1970s. It combines rhythm and blues with elements of disco, funk, soul, jazz, blues, electronic music, and hip-hop. Its distinctive features include smooth vocal arrangements, melisma, and hip-hop or dance-inspired beats.
Michael Jackson and Quincy Jones added electronic elements to the sound of the late disco era, creating a smoother, dancefloor-friendly style. Their 1979 collaboration Off the Wall was described by AllMusic as "a visionary album" that broke disco open into a new direction, balancing an undeniable beat with lush ballads and funk.
New jack swing is a style that combines R&B with hip-hop rhythms. Producer Teddy Riley began producing recordings in this style in 1986, and it was applied to artists such as Keith Sweat, Bobby Brown, Johnny Kemp, and Bell Biv DeVoe. Janet Jackson and her producers Jimmy Jam and Terry Lewis are also credited with shaping this direction through her 1986 album Control.
Whitney Houston's The Bodyguard: Original Soundtrack Album, released in 1992, became the best-selling soundtrack of all time. It eventually sold over 45 million copies worldwide.
Usher's Confessions, released in 2004, sold 1.1 million copies in its first week and over 20 million copies worldwide. It was certified Diamond by the Recording Industry Association of America after surpassing 10 million US sales, and it produced four consecutive Billboard Hot 100 number-one singles.
Electro-R&B is a subgenre defined by Apple Music as sitting "at the intersection of R&B and electronic music, creating abstract hip-hop that blends the moodier end of electro with minimal R&B beats." It developed from an earlier association with 1990s and 2000s groups like TLC and Destiny's Child, and became the genre's dominant direction in the 2010s through the use of Auto-Tune and computerized synthesizers.