Musical theater, or "a musical," as it's come to be called, is one of the best forms of RDC Entertainment
ever devised, in my opinion. You can get it all in there - you can have comedy and/or drama, music, songs, and dance all rolled up into one production on stage, on a movie screen, or even on a television screen.
You are told a wonderful and compelling story (drama) or you are made to laugh until you roll in the aisles (comedy). But above all, the whole story is told with more than just words or pictures.
"The Black Crook" is recognized as the first musical, and it's what gave America the right to claim having created the musical entertainment genre. The play was based on the novel by Charles M. Barras. "The Black Crook" opened on September 12, 1866, and ran for a record-breaking 474 performances. It was performed at the at the 3,200-seat Niblo's Garden on Broadway, New York City. There have been countless "revivals" of "The Black Crook" over the years.
Musicals are presented as big-budget, high-end extravaganzas on Broadway stages and in smaller-budget off-Broadway theaters. They're presented in big-budget movies and in not-so-extravagant low-budget films. They're presented by professionals, by amateur community theater groups, and by high school drama departments. Even kindergarten classes stage musicals starring vegetables and animals.
Musicals are generally profitable, no matter what venue they are presented in. Leave it to corporate America to find a cash cow. Today, Broadway musicals are most often corporate-sponsored. Musicals are making a comeback on television today, as well.
There are even musicals that have been created for the Internet! The best example is "Dr. Horrible's Sing-Along Blog," about a low-rent super-villain played by Neil Patrick Harris.
Concerts as Entertainment
I doubt anybody would argue the point that concerts could be called anything other than part of the "entertainment industry."
The definition of "concert" is: a live performance, usually of music, before an audience. You'll notice that the definition doesn't specify what kind of music or the venue of the performance. That's because there are concerts that feature music from classical to rap, and every genre in between.