Follow and following
When you follow another member, you are giving them your vote of confidence. Your saying that there is something interesting about them, perhaps that the events they run are good, their blog is interesting, their images are really nice or that you know them and they are just nice people to work with.
Whatever your reason, you will want to be able to find them again quickly, to see if they have added something new or interesting. So when you login they will be on your home, just waiting for you to have a look at their page.
TIP: The follow button, is below the main picture on their listing. To follow an organiser of an individual event you are looking at, click on the picture to view their listing with all their events on it (you will need to be logged in to do this).