The document discusses denial of service (DoS) and distributed denial of service (DDoS) attacks. It defines DoS attacks as attempts to make a machine or network resource unavailable to legitimate users. DDoS attacks specifically involve multiple devices in the attack. The document outlines different types of DDoS attacks and provides statistics on DDoS attacks from sources like Akamai. It then discusses best practices for preventing DDoS attacks, such as keeping software updated and monitoring networks, as well as methods for mitigating DDoS attacks, like traffic scrubbing services.