Not long ago, if you wanted music, you had to save up your pocket money, take a trip to the local record shop and lovingly leaf through its racks.
Now, it's almost all free, instant and infinite. And our relationship with music has changed forever.
We all know what the alleged future of music will look like. The record industry will be reduced to a smouldering ruin, the album replaced by endless individual songs and music rendered pretty much worthless by the fact that it's universally free.
Empty record shops will be overrun with weeds and old CDs will be used as coasters. Your Madonnas, U2s and Coldplays will prosper, but for anyone further down the hierarchy, the idea of making much of a living will be a non-starter.
That's the accepted wisdom, at least. Some of it will probably prove to be true.
But that grisly picture ignores subtler and more fascinating changes in our relationship with music that people have barely begun to understand.
Fans can instantly discover the Rolling Stones' 1980s works, if they want to
Now, just to make this clear from the off: I'm nearly 40. Having recently moved house and consigned my CD collection to cardboard boxes, I've been surprised to find that I don't miss it at all.
I use the free version of the music streaming application Spotify almost every day - and I now understand that it represents a genuine revolution in music consumption (and makes iTunes look pathetically old-fashioned).
Should the music industry finally get its act together and insist on some kind of subscription model, I'll pay for the same kind of service. But I wouldn't imagine that will alter my new listening habits.
All that said, my musical mindset is still rooted in an increasingly far-off past, where to be a true fan of a band took real dedication, access to obscure information - and, frankly, money.
I've just poured the music-related contents of my brain into a book, and I would imagine that 30-ish year's worth of knowledge about everyone from Funkadelic to The Smiths has probably cost me a five-figure sum, a stupid amount spent on music publications, and endless embarrassed moments spent trying to have a conversation with those arrogant blokes who tend to work in record shops.
Last weekend, by contrast, I had a long chat about music with the 16-year-old son of a friend, and my mind boggled.
What to listen to next: Little Richard or La Roux?
At virtually no cost, in precious little time and with zero embarrassment, he had become an expert on all kinds of artists, from English singer-songwriters like Nick Drake and John Martyn to such American indie-rock titans as Pavement and Dinosaur Jr.
Though only a sixth-former, he seemingly knew as much about most of these people as any music writer.
Like any rock-oriented youth, his appetite for music is endless, and so is the opportunity - whether illegally or not - to indulge it. He is a paid-up fan of bands it took me until I was 30 to even discover - and at this rate, by the time he hits his 20s, he'll have reached the true musical outer limits.
What does all this tell us? Clearly, for anyone raised in the old world, the modern way of music consumption has all kinds of unforeseen benefits.
A good example: though I've always heard plenty of talk about the utter awfulness of such infamous albums as Lou Reed's Metal Machine Music (a double album of guitar feedback and white noise) or Deep Purple's Concerto For Group And Orchestra (don't ask), I can now listen to them for nothing, and have an opinion of my own.
As one of my music press colleagues use to say, there's no longer any past - just an endless present
They're both terrible, incidentally, but that isn't the point. What really matters is the fact that I can so easily tune in - and what that says about a new world of completely risk-free listening.
Most importantly, as the great digital revolution rolls on, bands are no longer having to compete for people's money. Instead, they're jockeying for our time. And the field is huge, crossing not just genres, but eras.
Who do you want to investigate today: TV On The Radio or Crosby, Stills and Nash? Do you fancy losing yourself in the brilliant first album by Florence And The Machine, or deriving no end of entertainment from how awful The Rolling Stones got in the 1980s? Little Richard or La Roux? White Lies or Black Sabbath?
As one of my music press colleagues use to say, there's no longer any past - just an endless present.
U2's last album may have been a "grower" - but not many let it grow
For musicians, it's self-evident that there are all kinds of new openings for their music, but even if they break through, much less concerted attention will be paid to it.
They may get an audience, but it will be very easily distracted. After all, endlessly playing the same album so as to extract your "money's worth" is behaviour that will soon seem like something from the dark ages.
Woe betide the act that decides to make the kind of record that tends to be charitably described as a "grower" - something that may account for, say, the scant interest paid to the last U2 album.
Certainly, as a record company MD told me a couple of weeks ago, stuffing your albums with mere filler is no longer a sensible option.
So, yes, the record industry may yet have to comprehensively reinvent itself, or implode. Sooner or later, given that the need to read reviews before deciding what to listen to is fading fast, I rather fear that even music journalists may be rendered irrelevant.
But for now, this is a truly golden age - the era of the teenage expert, albums that will soon have to be full of finely-honed hits and the completely infinite online jukebox.
Even if the music business manages to somehow crack down on illicit downloading and claws back a few quid via annual subscriptions in return for that self-same endless supply of music, the same essential rules will apply. Really: what's not to like?
John Harris is the author of Hail! Hail! Rock'n'Roll, published by Sphere.