1. A sudden accident or a natural event that causes great damage or loss of life is called disaster.
2. Disaster management refers to a range of activities designed to mitigate the effects of disasters and to provide a framework to help people at risk.
3. The organization and management of resources and responsibilities to deal with emergencies so as to secure and safeguard the humans is called disaster management.
4. To deal with emergencies disaster management focuses on preparedness, response, recovery and prevention in a order to reduce the impact of disasters.

Explanation:

1. A disaster may be natural or man-induced, catastrophic or diastrophic may have originated in the interior of the earth or in atmosphere.
2. Some disasters like volcanic eruption, earthquake, tsunami, etc. occur due to the result of natural cases.
3. Irrespective of its form or origin its effect can be seen over a large area of the earth, causes devastation and takes lives of several people.
4. At times some disasters are pre-planned to cause devastation and destruction. For example, atomic attack by US bombers on Hiroshima and Nagasaki cities of Japan during the Second World War, terrorist attacks, riots, etc.
5. On the other hand some disasters occur due to human negligence or mistakes. For example, Bhopal Gas Tragedy, Chernobyl Atomic Disaster of Russia, etc.