ShowbizGreatest hits of all time... probablyBootylicious Beyonce's Crazy in Love is a pop 'must-have'.Pete Clark|Evening Standard12 April 2012In this dangerously fragmented music world, the fan is bombarded by a bewildering variety of sounds.The distance between the pioneers of rock and pop and the exponents of sonic mayhem is now too great to be traversed without a map.Fortunately, there is guidance at hand from Q magazine. It breaks modern music down into nine categories, from pop to electronic, via soul and reggae.Each genre is represented by a Top 20 "must have" tracks.The lists will either plug those gaps in your collection, or you can start arguing, which is much more fun.You might, for example, wonder at the exclusion of the Beatles, or for that matter, the Beach Boys. To include Baby One More Time by Britney Spears while missing out Strawberry Fields Forever is the act of people with Van Gogh's ear for music.I'm not an expert, but the rap selection looks a bit safe, while good old metal hangs in there, proving that big noise never goes out of fashion.Q Magazine is published on Thursday.MORE ABOUT50's US Rock And PopElectronicsNewspapers And MagazinesPeople MagazineReggae And Dub