How old are you? If you were very young in 1983 they were seminal and unlike any other band. If you discovered them in 1992, you were mainstream. If 2006 they were just a old band you didnt get into, that is fine.
If you loved college rock or post-punk they were the U.S. answer to so many questions on how mainstream music at that time was uncreative, boring or just didnt matter!
R.E.M. is the tent pole in my music life since I was 15, sounds corny and it may be.
If you dont get it is fine, they will be fawned over 30X more over the next year since they broke up, shame they are so much better than that and more worth while than web press. They broke up on their own terms and have a great legacy. There last few albums lacked, but they never gave up their craft. Many bands try so hard to hit their pinicle, REM just was who they were.
'Nevermind' might be the most important album for many, since the 90's are now back in style and the album more relevant in some areas. But in 1983 Murmur is a far more influeital album by far.
I Never got into grunge or you didnt get some other music or R.E.M.
All good and off my soap box!