A Denial of Service (DoS) attack is a malicious attempt to disrupt the normal functioning of a computer, network, or website by overwhelming it with excessive traffic or requests. This flood of activity can cause the targeted system to slow down significantly or become completely inaccessible to legitimate users. DoS attacks do not typically involve unauthorized access to data, but they can cause significant downtime, loss of productivity, and potential financial losses for organizations. Attackers may use various methods, such as sending large volumes of data or exploiting software vulnerabilities, to exhaust the system's resources and prevent it from serving its intended users.