Exactly slaw, Rock. The two are used interchangeably, as if they mean the same thing. They obviously do to younger dudes, but not to me. Here’s how I differentiate between the two:
Rock ’n’ Roll, or Rock & Roll, or Rock and Roll, is the combination of the music southern blacks were making after the end of WWII (Jump Blues, Rural Blues, Rhythm & Blues, Gospel), combined with the music southern whites were making at the same time (Hillbilly, Bluegrass, Country, Gospel). It sounds "southern", rural. That’s an over-simplification, as Big Joe Turner’s (out of Kansas City) "Shake, Rattle, & Roll" (from 1954, a year before Elvis Presley’s 1st Sun single) is very much Rock ’n’ Roll, and it contains no strains of "white" music. Same with the music of Little Richard and some other southern blacks.
But the black artists were being played only on stations catering to the ’Race" market. Sun Records owner/recording engineer Sam Phillips was recording black artists in the Memphis area for that market, including the great Howlin’ Wolf. What a voice! You’ve probably heard "Smokestack Lightning" (The Yardbirds did it), but not like Wolf sings it! Sam was quoted as saying "If I could find a white man with the black feel, I’d make a million dollars". Elvis Presley walked into Sun Records in 1954, and the world was about to change. By the way, it was because Rock ’n’ Roll was a mix of black and white that it was at first banned in the southern states. "We ain’t havin’ our white kids listenin’ to no n*gg*r music", was the attitude.
I wasn’t yet old enough to hear that original 1950’s Rock ’n’ Roll on the radio, but I DID hear Chuck Berry, The Everly Brothers, Roy Orbison, etc., whose music was sure Rock ’n’ Roll (R & R without Chuck Berry’s guitar playing? No way!), in the early 60’s. I was introduced to a lot of 50’s music by the British Invasion groups, who WERE old enough to have heard it at the time of it’s release. One of those groups was of course The Rolling Stones, whose music was much more informed by black music than by white. The same is true of The Animals, The Yardbirds, and some other BI groups. It was the elimination, or at least minimization, of the southern white influence in the music of those bands that created what I think of as Rock. It is much more Blues based than anything else; very little of the Hillbilly influence heard in 1950’s Rock ’n’ Roll. Also, Rock 'n' Roll has a hint of "swing' in it, the shuffle rhythm heard in some Blues and a lot of Country. Rock music is largely devoid of the swing/shuffle feel, every note having the same time value (musician's and listener's schooled in music theory know what that means).
Now here’s something I find amusing: One of the musical movements taking place largely under the radar in the late 60’s was the reintroduction of Hillbilly/Bluegrass/Country into Rock music (Dylan, The Band, The Byrds, others), music which was then referred to as Country Rock. See the humor in that?!
I saw a quote from Steven Tyler, saying their (he and the other Aerosmith members) ambition was to become The Rolling Stones. Who else finds that quite a pathetic admission? Isn’t to take the same influences and become your own version of it, rather than a copy of The Stone’s version, a much more noble and dignified ambition? I DO have to admit, though, they certainly achieved their modest goal. Embarrassing.