20 Jams is a selection of videos that stretches back to the earliest days of hip-hop, through to contemporary 2001 R&B. Interspersed with period examples of MTV links, it showcases the music channel's extensive coverage of black music, albeit after a slow start. Run-DMC and Aerosmith's superb Walk This Way is a kicking start to this compilation, a mid-80s first contact between hip-hop and heavy metal, with the video demonstrating Aerosmith's Steven Tyler and the laceless Adidas boys coming to a working understanding that would prove massively influential. The awesome but often overlooked Eric B & Rakim follow up, before De La Soul's mellow and colourful Me, Myself and I heralded another radical shift in hip-hop story, wittily going back to a classroom setting to teach us the new style. Digable Planets and a George Clinton-like Humpty Hump offer their own stylistic divergences but then, as the video enters the 90s and beyond, it concentrates on some of the blander, less inventive, pop tendencies of R&B: Juvenile offers us every video cliché in the book; Monica's offering is visually drenched in the soft, dreary beige of her soft, dreary, beige ballad; while Method Man's interview segment, You gotta make it look good ... nice and presentable ... sell more albums, is in miserably stark contrast to the invention of the hip-hop pioneers. Thankfully Erykah Badu, playing the role of harassed housewife-cum-diva in the video to Rimshot, redeems the next generation. --David Stubbs