Classic Rock is an essential in my life. Only God & my loved ones rank ahead of it. Ever since I was young, I've loved classic rock with a passion. My dad introduced me to The Beatles when I was about five or six, and for awhile, they were my favorite band.
As the years went on, I began to discover great artists / bands like Heart, AC/DC, Def Leppard, Guns 'N' Roses, Bob Dylan, The Grateful Dead, Simon & Garfunkel (not sure if they qualify as classic rock, but they're one of my all time favorites), Black Sabbath, The Cars, The Rolling Stones, Neil Young, Elton John, David Bowie, The Police, Meat Loaf, Pink Floyd, The Beach Boys, Eric Clapton, The Doors, Fleetwood Mac, Van Halen The Clash, The Ramones, Jimi Hendrix, Billy Idol, Journey, Queen, The Who and the best band of all time, Led Zeppelin. I've probably left off a lot of bands, mostly because I have a fairly vast collection.
As for the 1980s, the 1980s' brought us Guns 'N' Roses and Def Leppard, not to mention (well, it was already mentioned) AC / DC's Back In Black. GNR and DL released the two best albums of the decade, Appetite For Destruction and Pyromania (Hysteria also gets an honorable mention).
This is just my two cents.