To begin with, Buyers must buy books from the secure site to prevent themselves from being cheated. (2.1.1)The main reason for this is buyers take risk for credit card fraud in some case, buyers trust online sites too much and do not make sure that it is the secure or insecure site. (2.1.2)In addition, buyers also take risk for not getting the books they buy such as lost in transit or seller earns money and escape. That makes many people still do not dare to risk to buy books from the site.