To borrow from Bob Segar, Rock and Roll soothes the soul. And Rock would excite the soul. (and I only half believe that)
Howzabout rick-roll music?
Gotta be Rick-Roll music, if ya wanna piss me off.
Rick-Roll music will make me want to run around and desert you.
So literally, am I the only one on the planet who actually likes that song?
My take: both terms are extremely generic and basically mean “popular music released in the Anglosphere and aimed at adult audiences”. “Rock and Roll” is slightly more likely to refer to the traditional guitar-bass-drums setup, but only slightly. The genre of Little Richard and Jerry Lee Lewis is “old-time rock” or “rockabilly”. Even hip hop is a subgenre of rock, for which I cite Run-DMC crowning themselves “Kings of Rock”.
This is how I remember the situation at the time. Rock and roll was, actually, sometimes mocked and derided as “greasy teenage sockhop music”. Rock was more serious, exploratory, and politically/socially relevant. It had messages to send and lessons to teach. ISTM that the musicians who had grown up with the earlier genre generally continued to admire the 1950s musicians who had inspired him, but casual fans were a lot less tolerant of anything “old”, and this was a time when music was changing so fast that “old” could mean three months before.
Today ISTM people use the terms interchangeably, however.
I think it’s kind of amusing that Peter, Paul and Mary’s “I Dig Rock And Roll Music” isn’t rock and roll at all.
This is the first post that has me questioning my original assertion that the terms are synonymous. Great post! By these definitions, I would probably put the birth of rock around 1967, Give or take a year or two.
I’m reminded here of the scene in Quadrophenia where one guy is singing Be Bop A Lula and the other tells him it’s rubbish and starts belting out You Really Got Me. Gene Vincent vs The Kinks / Mods vs Rockers.
I don’t think anybody is disputing that music in 1960 was substantially different than music in 1970. The debate is whether this difference represented a substantial change within an existing genre of music or the creation of a new genre of music.

I don’t think anybody is disputing that music in 1960 was substantially different than music in 1970. The debate is whether this difference represented a substantial change within an existing genre of music or the creation of a new genre of music.
I would say it’s on the cusp between the two?
50s rock-&-roll was very obviously different from a decade earlier, perhaps because the guitar became a principal instrument rather than horns etc.
One can argue I suppose that the change from there to 70s rock was more evolutionary than revolutionary, driven by the advent of effects like distortion on the lead guitar etc, plus evolution of the lyrical style beyond basic romance songs.
It’s all starting to fade into the past anyway: ‘classic rock’ is now almost as fossilized a genre as ragtime or Trad Jazz…
I think it’s also clear that people in, say, 1970 definitely felt that music was changing in radical ways and dramatically breaking with the past. The question is whether that perspective makes sense from our point of view.

I would probably put the birth of rock around 1967, Give or take a year or two.
I’d say 1966 at the latest; we have to include *Revolver*.

I mean, blues has a fairly defined structure to it: 12 bars, I-IV-V chords, songs are usually in the form of a line of the verse, a repeated line of the verse maybe with a minor variation, a conclusion to this line.
I love ya, but no. That’s something done to formalize the form after the fact. Most blues songs that adhere to the 12 bar format are copycat nonsense, or rock 'n roll songs. Most of the ones I love almost never adhere to that format. My favorite blues song has nothing to do with it, it’s basically a one chord vamp with a break. It’s the bluesiest thing since blues came to blues town.
And well, Rock 'n Roll vs Rock is a very vague argument of terms. The Cramps were using a similar I-IV-V format, but a decidedly not really teenybopper loony perspective. They’re obviously Punk Rock, but are they Rock or are they Rock 'n Roll?

And is death metal distinct than doom metal?
oh, now you done it Oh yes, very much so,
Stoner/Doom Metal almost always intentionally sounds like it could almost be, but not quite a Sabbath cover. So basically the first time you could no longer deny Heavy Metal existed, the first metal band was a doom metal band. Might as well listen to the first few Sabbath records, but some folks want variety within a specific genre they’re comfortable with (and sometimes that folk is me).
Sleep were going in a similar vein some 25 years later,
Death metal is normally much, much faster, less loose, heavily produced and at least verging on the land of the Cookie Monster. I can take some Cookie Monster, but the other folks better be doing something interesting.
Once you’re kinda versed in the forms, it’s easy to tell them apart. But then you run into something like Melvins, where sometimes they might as well be pop, power metal, some really screwed up version of hair metal, or just the thrashiest thing since thrash came to thrash town.
Or you know, the metal version of “watching dough rise”? (probably the doomiest Melvins ever were)
I’m kind of sure that the first Melvins song is rockin’, and possibly is Rock ‘n Roll. I’m almost sure the second is rockin’, but it’d be a stretch to call it Rock 'n Roll.