The number of PC and Internet users has risen rapidly in recent years. Unfortunately the growth in IT know-how has not automatically been matched by a rise in security consciousness among Internet users. Although there are now numerous technical aids available that protect the user reasonably effectively against interference from outside, absolute security is not possible - one must always be clear about that. Moreover, security is above all dependent on the user's own behaviour. Because of this, we have taken the opportunity to compile a range of useful tips that should help you to recognise the risks and to take the required precautions.