What are mutual friends?

When someone adds you to their network list, that person is your
fan and you are their favorite (and vice versa if you add someone to your network list). If you both add each other to your network lists, you are then considered mutual friends. You can tell who you are fans or mutual friends with by looking at the icon under each person's name in the friends list in your profile. Remember, you can always control your privacy settings to limit the display of personal information in your Profile.