Just because Paul McCartney is one of the biggest rock stars on the planet doesn't mean all music fans automatically know who he is.

For proof, look no further than the response that 'Only One,' McCartney's recently released collaboration with Kanye West, has gotten from a handful of Twitter users who don't have any idea who the former Beatle is -- but are expecting him to get a big leg up in his career now that he's been given a boost by one of hip-hop's hottest artists.

Some folks are predictably pretty upset about this, but it's the way pop culture has always worked; just because McCartney helped lay the foundation for much of what the kids of today are listening to, that doesn't mean they're necessarily going to know it -- the same way the millions who bought Beatles or Rolling Stones or Led Zeppelin LPs weren't obligated to research their favorite bands' influences.

Of course, it's always good to dig a little deeper into the music that moves you, and it probably bears mentioning that it's never been easier or more affordable to map an artist's musical DNA (or just, you know, Google "Paul McCartney"). Still, these tweets highlight exactly why McCartney has always been so enthusiastic about branching out into areas like film, television and video games: No matter how big you are, there's always a new audience for you. Clearly, McCartney's just found another one.

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