DoS (Denial of Service) is an attack orchestrated through multiple computers positioned in the same location or building. Whereas DDoS is an attack in which multiple computers from different geographic locations will flood a web application or network services with so many requests it can barely handle. These unsolicited requests will render the victim systems to slow down or eventually to crash altogether.
The attacker may apply hundreds of thousands or millions of infected computers known as botnets to achieve sophisticated DoS/DDoS attacks. Moreover, these botnets are a network of infected zombie computers (bots) controlled by a botherder or botmaster.
the_cyberguy Answered question 10/07/2022