The motivation for the malicious tasks accomplished with a botnet – spam distribution, DDoS attacks, pay-per-click fraud, and so forth – tend to fall into two categories: financial gain and to make a point. Spam e-mail is often used to advertise goods for sale, especially black-market prescription drugs. Pay-per-click fraud is often committed to earn advertising commissions for fraudulent clicks. DDoS attacks may either be an extortionary tactic to secure a website ransom, or as a means to prove one’s mettle as a black hat hacker.