Questions all about sororities!?

My friend and I are both in high school and going to be applying to colleges soon. We were talking about it, and the subject of sororities popped up. Due to movies and stories from friends and family, we feel that sororities have a certain negative connotation to them; so I've decided to ask the Yahoo community: What do you think of sororities? Are they really as bad as some people make them to be? Are girls that join slightly shallower? Why would someone join in the first place? What are the advantages/disadvantages? Are there rituals and pledges to follow?