Hard Rock is just classic rock that's often a little too hard and rocking for the ladies who prefer more mellow stuff which is cool.Classic rock includes any rock from the 60's and 70's such as psychedelic rock,acid rock,hard rock,progressive rock,progressive hard rock and maybe some metal before it became such a trendy fad and before Mtv fagged it up beyond repair and the underground dicks didn't help either with the possible exception of "some" thrash metal.Classic rock was more blues influenced and soulful than today's metal which is too stiff and stupid and dark and goth and evil to be enjoyable.

Let's do this right with no faggy hair metal or grunge tards...

Led Zeppelin
Rush (started out as hard rock and hard progressive rock)
Ted Nugent
Aerosmith
AC/DC
Nazareth
Heart
BTO (listen to songs like "Not Fragile" and "Welcome Home")
BOC
Thin Lizzy
UFO
Scorpions (old stuff before the dark times,before metal)
Cream
Black Sabbath
Alice Cooper
Queen (if you don't think so it's because you haven't listened closely enough)
Deep Purple
Ozzy with Randy
Jimi
Van Halen (the original Van Halen only)
Pat Travers
April Wine
Triumph

Hard Rock is very closely associated with rock,classic rock,progressive roc...