This book summarizes several researches and reports about spam. Many users underestimate the losses caused by spam and assume the severity of the problem by the amount of spam they receive in their inbox. However, the total worldwide financial losses caused by spam are estimated at several billion USD per year. The problems of spam include impacts on businesses, stress, phishing, loss of corporate assets, inconvenience for the individual users, contribution to the carbon foot print of IT (or global warming), legal issues and exposure to viruses, spyware and Adware to name a few. Research...