When you think of pledging, it's likely hazing is the next thing that pops into your mind. Most universities and colleges define hazing in a similar way; Dartmouth describes it like this:
Hazing can happen in any organized group including sports teams and military groups. On college campuses, it tends to be a bigger problem in fraternities, but it certainly also happens in sororities. Most universities have specific rules forbidding hazing, and every sorority's national organization forbids hazing as well. Despite these restrictions, hazing is still happening on campuses throughout the United States.
Hazing in a sorority might include forcing pledges to go without sleep, forcing them to binge drink, scaring them or forcing them to do degrading tasks. Stories circulate about girls being told to bring markers with them to meetings. Sisters use the markers to circle areas of the pledge's body to indicate where they think the pledge needs to lose weight. Universities and national umbrella organizations take hazing very seriously -- and for good reason as hazing has resulted in injury and even death. Because it is such a serious concern, each school has a system to handle hazing complaints.
If a potential new member meets all of her pledgeship requirements, she may be eligible for initiation, a secret ritual event during which she will become a full member of the sorority.
During initiation, she will learn the sorority's secrets, from the secret meaning behind the Greek letters to secret passwords and secret handshakes. Yes, lots and lots of secrets. Marking the transition with a special ceremony, which has been upheld for decades or even a century, is meant to have a powerful effect on the initiate, tying her to a tradition, the ideals of the founders and an idea of sisterhood. These rituals often have ties to Greek secret society rituals and involve symbols, and perhaps even costumes. Sisters are forbidden to reveal the sorority ritual or its secrets.