Here's a free extra cup of coffee. Consider it a refill on the house.

Today's Elvis Presley's birthday. Were he still alive he'd be 72.

If you were born anytime after the Vietnam War ended you probably don't really understand why he was such a huge deal, much as you probably wouldn't think a Model T Ford was such a big deal, as cars go. To you he's a schlocky punch line. Thanks to whoever approves such products as Elvis hula lamps and Elvis toilet seat covers I can see why you think that.

The whole point of Elvis, though, is that he was the first to kick the door open. Pointy-headed rock critics quibble endlessly about who recorded the "first" real rock and roll, reaching as far back as Louis Jordan and earlier. Usually what they bring forward as the "first" rock record, "Rocket 88" or whatever, is an exemplar of one strain of influence on what became rock itself, like someone claiming either oxygen or hydrogen was "the first water."

It's all academic. Elvis was the first one who brought the primary influences of rock 'n' roll -- being country and western on one side and rhythm 'n' blues on the other, his records were first played on black radio stations and first charted on country charts -- together, and used his personality and charisma, essential qualities quickly forgotten by those who focus on minutiae and lose the big picture, to create a new cultural phenomenon the likes of which hasn't been created since.

Think of him as the test tube where all the right amounts of the right chemicals for the right explosion were combined for the first time.

Slice and dice it any way you want to, there's no getting around Elvis Presley from 1954 to 1956 as the founder and the most important figure in rock history -- the one who made "race records," as music by black artists was called then, respectable to white audiences, and brought what were dismissed as "hillbilly" records to public awareness. You know "hillbilly" as "country" today.

But there's the actual matter of the records, the vast majority of which are little more than money-generating dreck. Here's what you do to understand what the big deal is:

Listen to the 1954 Sun sessions, available on iTunes. Get "That's All Right," "Milkcow Blues Boogie," "Baby Let's Play House," "Mystery Train" and "Blue Moon of Kentucky," as well as "Good Rockin' Tonight," which put you at the Lexington and Concord of rock 'n' roll. They'll sound quaint, tame and unexciting today. So listen to any other popular charting records from 1950 to 1954, and listen to the charting records in 1955, 1956 and on. You'll begin to get an idea what the big deal with Elvis was. Completely new thing.

Get his debut album, titled simply Elvis Presley, with the green and pink lettering. Try to find any worthwhile rock act since with no influences drawn from that album. Get those songs you've heard the names of -- "Jailhouse Rock," "Hound Dog," "Don't Be Cruel," "All Shook Up," et al, and for comparison's sake listen to other pop records from those years. See the difference?

Finally, to hear him at his musical peak, get From Elvis in Memphis, his 1968 album. Granted this one isn't one of the great rock albums, it's not even one of the five best albums of 1968. But it's the best album he ever put together. It doesn't matter that by this time he had been surpassed by The Beatles, Rolling Stones, Bob Dylan, The Supremes, The Beach Boys and other acts, if it wasn't for him it's not sure any of them would have existed in the first place.

Not to say he was a museum piece after 1962, he made records later in his career that stand with any in rock -- "Suspicious Minds," "Kentucky Rain," "Burning Love," "Viva Las Vegas," "In The Ghetto," the sublime "Can't Help Falling In Love With You." It's just that he wasn't the unchallenged King any more, his followers had come into their own.

I don't play Elvis all that often on my iPod. I have him on it, sure, but there are many other acts I listen to a lot more frequently. Nobody's saying you need to enjoy Elvis as much as you enjoy today's music, any more than you need to drive a Model T Ford today.

But understand that just as the Model T had to come before the Dodge Viper, there are probably four or five acts (oh, Elvis, Chuck Berry, Jerry Lee Lewis, James Brown, Buddy Holly, pick any other one you want. Little Richard? Hank Williams? Fine.) without which today's music wouldn't exist as it does, and that of those, Elvis is the most important -- that without him, it's a fair question if much of anything on your iPod, be it country, funk, rock, rap, R&B, punk or whatever, today would be there at all.

Now back to your regularly scheduled Beyonce and Red Hot Chili Peppers.