by Amarilis Gibeli (About.com Expert Contributor)

On one hand, Glam Rock, or Glitter Rock, was a '70s amalgamation of Hard Rock riffs, Pop/Soul melodies and (most importantly), over-the-top sexual ambiguity, gaudiness, theatrical makeup, costumes, props and attitude. Ziggy Stardust era David Bowie, Roxy Music, The New York Dolls and "Bang a Gong" T.Rex were major innovators and torchbearers for this short-lived but highly influential genre. Both Heavy Metal and New Wave borrowed and adapted liberally from the Glam Rock ouevre, as well as the free-range of the Alternative rock genres. While the term Neo Glam never merited a proper nickname in the music press, this first wave of Britpop gave new life to England's sagging music scene in 1993. Feeding off early ‘70s glam rock — along with all variety of non-grunge alternative rock — Pulp, Suede, and the Auteurs led the pack of smart, melodic guitar acts in thrift shop clothes. Sexual imagery and gender-blurring abounded (particularly with Suede), paving the way for bands like Placebo, Mansun and Gay Dad years later.

The term "Britpop" was born in the UK press around the time Blur's Parklife was released (1994), the same month Kurt Cobain died, incidentally. The bands like Pulp, Charlatans, Lush, varied in sound, but whether they were inspired by punk, new wave, glam, mod, or any combination of these, they all had glamour, a pop flavour, a typically British cleverness and a love of Britain's rich rock ‘n' roll past. Britpop became less common after 1997, with many of its key figures fading away or changing paths, but bands like Catatonia and Rialto have since picked up the torch.

One of the recently glam-rock revivalists is the Alternative rock CD released last year by Conspiracy Music titled "Blockbuster" - a 70's glam-rock tribute album. It includes a pair of David Bowie songs and a pair of T. Rex songs, as Cyclefly cover the former's "Five Years" and Otherstarpeople take on "Suffragette City". Former Haircut 100 frontman Nick Heyward covers the latter's "Hot Love," and Dramarama offer up "Raw Rump." The Donnas' - the girl-group whose members all suspiciously claim to be called Donna - offer up a rendition of the Sweet's "Wig Wam Bam". At least, a curiosity.

On the other hand, Alternative, or Alt. Rock, is a very broad and rather vague term. Originally it encompassed almost any post-punk, non-mainstream music, from REM and the Pixies to XTC and Fugazi. In the early '90s, thanks to the success of Nirvana, Sonic Youth, and The Red Hot Chili Peppers (mostly Nirvana), the lines between Alternative and Pop were blurred. Pop bands adopted Alternative trappings and Alternative bands were marketed to Pop audiences. Everything from the faux arena Rock of Soundgarden to the retro-pop of Smashmouth is classified as Alternative these days. Actually I share the idea that once your 14 year old little sister gets over N'Sync she will be totally into Alternative Rock.

It was popularized in the late 1980s, the era of early alternative rock, when bands created emotional realism, and left the big hair and double gripped, head banging monster ballads at the door, making stand-out groups like R.E.M., combines heavy-metal guitars, folk and punk influences, and cryptic, introspective lyrics. The alternative style spawned a number of substyles, such as the grunge rock of Seattle-based groups Nirvana, Soundgarden, and Pearl Jam, with bands such as The Smashing Pumpikins, Stone Temple Pilots have shown us what emotion can do for rock and roll. The culture of respect for women, gays, minorities, cultivated by powerhouses, like Nirvana for instance, has given way to an atmosphere of intolerance that suggests we were not on the doorstep of a new century, but trapped in Alabama, circa 1954. This rock style has developed through a large "family tree," which traces the interwoven strands of such genres as Punk, Glam Rock, Industrial, Hip Hop and Grunge, which the alternatives artists, even today, continue to push rock toward new horizons.

It shouldn't be left unsaid the College Rock, essentially the (largely) alternative music that dominated college radio playlists from the rise of alternative rock (circa 1983-84) through the '80s. Most college rock was born in the confluence of new wave, post-punk, and early alternative rock. College rock's poppiest bands didn't fit into the mainstream the way new wave did, and where much early alternative/American underground rock was rooted in punk and hardcore, not all college rock necessarily was. Early college rock's two most influential groups were R.E.M. and the Smiths, who paved the way for countless practitioners of jangly guitar-pop from the U.S. (the dB's, Let's Active) and U.K. (Housemartins, La's). There was the burgeoning, post-hardcore American underground rock scene (Hüsker Dü, Sonic Youth, the Minutemen, the Meat Puppets, Dinosaur Jr., the Replacements); the quirky, cerebral British pop of new wave survivors XTC and Robyn Hitchcock; similarly quirky American artists like They Might Be Giants, the Violent Femmes, Camper Van Beethoven, and the Pixies; literate folk-rock (Billy Bragg, Waterboys, 10,000 Maniacs); post-punkers who added more pop dimensions to their music (the Cure, Siouxsie & the Banshees); synth-based dance-pop with moody, introspective lyrics (New Order, Depeche Mode); and bands who blended pop hooks with ear-splitting guitar noise (the Pixies, the Jesus & Mary Chain). College rock also included a few mainstream stars like U2, Peter Gabriel, and Sting, whose thoughtful lyrics and socially conscious idealism made them favorites on college campuses. College rock's heyday essentially ended with Nirvana's breakthrough in 1991, which opened mainstream ears to the more accessible side of alternative rock; as college radio playlists began to resemble commercial alternative radio, the more experimental branches of alternative and indie rock were driven even further underground.

Prior to Nirvana, alternative music was consigned to specialty sections of record stores and major labels considered it to be, at the very most, a tax write-off. After the band's second album, 1991's Nevermind, nothing was ever quite the same, for better and for worse.

Below some interesting resources regarding those topics:

Barnes And Noble
Glam Punkrock