Today, many people share personal information through online social networks. While these networks offer tremendous facilities to share one's life with family, friends and the outer world, users are also exposed to the risk to get their accounts compromized, with consequences for their professional and private lives. A strong password can help to ensure privacy, while in contrast, a weak password may lead to a compromized account. On the other hand, it is observed that users tend to shortcut laborious and time-consuming security measures, which alleges that their perception of their safety on the social network might deviate from the real safety situation. In this article, we investigate how users of social networks perceive safety, and to which extent they contribute to it. First, we examine the question in which way and to which extent a user's perception of safety is affected by increased response times. An investigation was conducted for teenage users of the online social network Facebook. Its results indicate that the users' perception of safety differs significantly in face of increased response times that usually imply worse Quality of Experience. Second, in order to find out to which extent users are aware of the risks associated with weak passwords as well as what measures have been taken to keep themselves secure and to ensure privacy, a survey about password complexity in online social networks was conducted with Swedish users. Our results of the survey indicate differences in password complexity between teenagers with different levels of technical education.