Botox is a trade name for Botulinum toxin which is a protein and neurotoxin formed from bacterium Clostridium botulinum. It is used to remove wrinkles.
Botox is name given to the toxin from this bacteria as said by Ruchita. It works by blocking signals from the nerves to the muscles. The injected muscle can no longer contract, which causes the wrinkles to relax and soften. It is most often used on forehead lines, crow's feet (lines around the eye) and frown lines. Wrinkles caused by sun damage and gravity will not respond to Botox.