That big colourful splodge, just above these words? That's all of pop history, that is. Well, all of pop history according to Google. Or, to be more specific, all of pop history according to Google Play users. Or, to be even more specific, all of pop history as defined by what Google Play users have in their music libraries.

It's Google's new Music Timeline, which searches Google Play users' libraries to see which artists they have music by. Artists are then categorised by genre, and genres subdivided. What it provides, then, is a rough-and-ready map of the popularities of genres and artists over the years. Bear in mind, it's not logging what people listen to, but what they own. And equally, note that Google Play users are a pretty small subset of music fans.

So let's take a couple of specific examples and see what it turns up. First, we'll look at the Rolling Stones.

That graphic looks like a pretty fair representation of the Stones' career. A burst of enthusiasm for the early albums, tailing off towards Their Satanic Majesties, then a huge spike for the run of Beggars Banquet, Let It Bleed, Sticky Fingers and Exile on Main St. And then a dramatic drop off, fading to an almost complete lack of interest in anything they have recorded since 1990.

But that's a canonical group, with a career arc that most people agree on (I'd say Goat's Head Soup is as good as the four albums that preceded it, but you won't find many sane people who'd stick up for Black and Blue or A Bigger Bang as among the Stones' defining albums, I suspect). Of course, Google Play users are more likely to own the most famous albums by one of the world's greatest groups than they are to flock in numbers to missable late-career albums. But what happens when we look at a genre? Let's try punk.

As someone who believes the first three Ramones albums to be pretty much the apotheosis of western civilisation, I'm delighted to see what a huge presence they have on this map. But this division of punk's early years into Ramones and the Clash ignores history: it rewards them for releasing several albums in quick succession, and penalises the Sex Pistols for only having released one "proper" record. What's more, we can speculate that Google Play is disproportionately popular in Germany, thanks to presence of Die Ärtze and Die Toten Hosen, who are owned enough among Google Play users to get a namecheck. What the punk chart actually looks like isn't a graphic representation of the music's popularity and influence, but a marketing presentation for one of those Best Punk Albums in the World … Ever! albums, the names being the motley selection the label was able to license rather than the groups that matter. And so to soul and R&B.

Who knew? Soul and R&B can be scientifically proven to be at their best in 1960. All of which might come as a surprise to those countless millions who love Motown, or Stax//Volt, or Atlantic's great late 60s albums, or the Philly sound of a decade later, or … well, insert your soul/R&B golden age here, to be honest. What does it mean? That there are shedloads of early-60s soul/R&B comps on Google Play? That Google Play users think soul stopped evolving with Sam Cooke, or that James Brown's early records are miles better than when he got dead on the heavy funk a few years later? The other thing that's interesting is how static the graph is over the past 30 years – the libraries surveyed have an even spread of soul and R&B from that period.

So, a flawed tool, certainly. But by God you could waste hours fiddling with this stuff!