This document discusses disasters from several perspectives. It defines disasters according to the WHO as events that cause damage, disruption, death or deteriorated health services on a large scale requiring outside assistance. Disasters are categorized as natural or man-made, with examples of each type provided. The document also outlines levels of disasters from massive to minor, resources for disaster response, principles of disaster nursing including triage, and strategies for disaster planning, management, and preventing disease outbreaks in affected populations.