Generic tags in any branch of the arts are ad hoc most of the time and as often as not they are unsuited to the job that they do but nowhere is this so much the case as with music. The great Marxist critic Theodor Adorno in his book The Culture Industry back in the 1930s, declaimed the recent coining of the term 'classical music', which he termed 'barbarous'. Adorno believed that there was only 'serious' and 'light' music in the world. Which is not all different from what Kurt Cobain said sixty years or so later when he dismissed the term 'alternative' music; as far as Kurt was concerned, the only acceptable 'alternative' music was an alternative to bad music. Adorno did not care much for popular music, or at least not the type that was beginning to be mass-produced by the still-young recording industry. I have read many desperate rationalisations of Adorno's views by cultural studies academics, terrified at their very field of study being called into question by one of their heroes; these poor folk point out that Adorno died in the late 60s and may not have had the opportunity to listen to the Beatles to change his mind. And people always point out that his dislike of jazz was based on exposure to the worst type of white-boy swing jazz. It is irrelevant what Adorno might have thought of 'A Day In The Life' or 'A Love Supreme'; the core of his argument, that our music literacy and capacity for musical understanding has been irremediably damaged by mass culture, holds true.
But back to the tags, those labels that people put on popular music. Rock n' Roll is the one we all remember but has long lost its roll, and rock has split up into subgenres of heavy metal, speedcore, grunge, trash metal and so on. 'Alternative' and 'indie', redolent as they are of spotty male students with bad dress sense and dubious personal hygiene, has always been a turn-off for me - or at least since I answered to the description above. 'Electroclash' is a newer one, which is not bad but it makes it a bummer looking for 'London Calling' on your iTunes. In fact it is iTunes that brings the whole labelling of music genres into question; if you've got hundreds of different genres on your iPod or iTunes, as many people do because the tags and files come from all different sources, it is almost impossible to ever hear songs again if you shuffle genres. Because computers, seeing the world in 0s and 1s, do not really care too much for the difference between Merengue and Salsa. Just that insulting, blanket term 'World' works (surely a modern counterpart for Adorno's barbarous 'classical' music). Music will eventually be rationalised to the hilt by official terms such as iTunes official terminology: 'Alternative & Punk', 'Electronica & Dance', 'HipHop & Rap' etc. And no matter how fresh the term might once have been, it never sounds right to describe the music it purports to. I used to know a wealthy Californian girl who opined that Björk was the 'most punk-rock singer there was'. Whatever you're having yourself.