What is grunge?

Music scene from Seattle that produced some pretty good music

baby don't hurt me!

I legitimately believe grunge had some glam-metal roots.

Last relevant wave of rock music with britpop

Listen to Alice in Chains' material from before Facelift
You can definitely hear it

look up alice n' chains, formerly known as sleaze

...

It was a label placed on music that had a very specific sound that mostly originated from Seattle music scene in the mid to late 80's. It was just called Alternative Rock, or College Rock, until Nirvana went big [Or at least that's the impression, based off of documentaries like HYPE! or Pearl Jam Twenty, etc. Most bands called grunge hated the term, but the bands that embraced the term, like Silverchair, or Candlebox were coined as Post-Grunge. Listen to Melvins' Bullhead, Sonic Youth's Goo, Soundgarden Fopp, Pearl Jam's Ten, Mudhoney's superfuzz bigmuff, and Gas Huffer if you can find it. The genre's roots had a lot of glam metal, hardcore punk, art-punk and area rock influences. It was also dead before it was called "Grunge," as the genre never progressed.

what is the best grunge band?

*laughs*
It's... it... so cute