Dry ice is the solid form of carbon dioxide (CO2), comprising two oxygen atoms bonded to a single carbon atom. It is colorless, with a sour zesty odor, non-flammable, and slightly acidic.

Dry ice is frequently used for food preservation in non-cyclic refrigerators and in packing biological samples or other things which are to remain in cold. It is also used in ice-cream production and sometimes in medicine (for example in warts removal).

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