1. A disaster is a natural or man-made (or technological) hazard resulting in an
event of substantial extent causing significant physical damage or
destruction, loss of life, or drastic change to the environment. A disaster
can be ostensively defined as any tragic event stemming from events such
as earthquakes, floods, catastrophic accidents, fires, orexplosions. It is a
phenomenon that disasters can cause damage to life, property and destroy
the economic, social and cultural life of people..

2. TWO TYPES OF DISASTER:
 NATURAL DISASTER
A natural disaster is the effect of the earth's natural hazards, for
example flood, tornado, hurricane, volcanic
eruption, earthquake,heatwave, or landslide. They can lead to
financial, environmental or human losses. The resulting loss depends
on the vulnerability of the affected population to resist the hazard, also
called their resilience. If these disasters continue it would be a great
danger for the earth.[1]This understanding is concentrated in the
formulation: "disasters occur when hazards meet vulnerability."[2] Thus
a natural hazard will not result in a natural disaster in areas without
vulnerability, e.g. strong earthquakes in uninhabited areas.[3] The
term natural has consequently been disputed because the events
simply are not hazards or disasters without human involvement.[4] A
concrete example of the division between a natural hazard and a
natural disaster is that the 1906 San Francisco earthquake was a
disaster, whereas earthquakes are a hazard. This article gives an
introduction to notable natural disasters, refer to the list of natural
disasters for a comprehensive listing.