What do you think of indie rock or "alternative rock"?
I like it! It's a nice change from the classic rock I normally listen to! Can you recommend a good group?
I'm a big fan of Green Day. They are an alt rock group. 
I didn't realize they were considered alt rock! I listened to them a lot back in the 90s!  When do you think alt rock got started?
It started with grunge and punk revival bands in the US and UK. Even though those bands became mainstream they still maintained their underground and outsider attitudes. 
That's really interesting!  So I guess a lot of different bands could fit that definition. Is there still a big market for alt rock music?
I think so because some times the term alternative rock gets used for music that just doesn't fit in a category like pop or rap.