A snake is a long cold blooded, scaled reptile. All snakes are carnivorous and can be distinguished from legless lizards by their lack of eyelids, hind limbs, external ears, and the presence of only vestigial forelimbs. Snake live on every continent except Antarctica. While venomous snakes comprise a minority of the species, some possess potent venom capable of causing painful injury or death to humans. However, venom in snakes is primarily for killing and subduing prey rather than for self-defense.
In Egyptian history, the snake occupies a primary role with the Nile cobra adorning the crown of the pharaoh in ancient times. It was worshipped as one of the gods and was also used for sinister purposes: murder of an adversary and ritual suicide (Cleopatra).
In Greek mythology, snakes are often associated with deadly and dangerous antagonists, but this is not to say that snakes are symbolic of evil; in fact, snakes are a chthonic symbol, roughly translated as 'earthbound'. The nine-headed Lernaean Hydra that Hercules defeated and the three Gorgon sisters are children of Gaia, the earth. Medusa was one of the three Gorgon sisters who Perseus defeated. Medusa is described as a hideous mortal, with snakes instead of hair and the power to turn men to stone with her gaze. After killing her, Perseus gave her head to Athena who fixed it to her shield called the Aegis. The Titans are also depicted in art with snakes instead of legs and feet for the same reasonthey are children of Gaia and Ouranos (Uranus), so they are bound to the earth.
India is often called the land of snakes and is steeped in tradition regarding snakes. Snakes are worshipped as gods even today with many women pouring milk on snake pits (despite snakes' aversion for milk). The cobra is seen on the neck of Shiva and Vishnu is depicted often as sleeping on a seven-headed snake or within the coils of a serpent. There are also several temples in India solely for cobras sometimes called Nagraj (King of Snakes) and it is believed that snakes are symbols of fertility. There is a Hindu festival called Nag Panchami each year on which day snakes are venerated and prayed to.
In Christianity and Judaism, the snake makes its infamous appearance in the first book (Genesis 3:1) of the Bible when a serpent appears before the first couple Adam and Eve as an agent of the devil and tempts them with the forbidden fruit from the Tree of Knowledge. The snake returns in Exodus when Moses, as a sign of God's power, turns his staff into a snake and when Moses made the Nehushtan, a bronze snake on a pole that when looked at cured the people of bites from the snakes that plagued them in the desert. The serpent makes its final appearance symbolizing Satan in the Book of Revelation:"And he laid hold on the dragon the old serpent, which is the devil and Satan, and bound him for a thousand years." (Revelation 20:2)
Snake tattoos symbolizes power, both natural and supernatural, fertility, regeneration and wisdom. In the West in particular, the snake represents temptation and feminine sexual power. One of the reasons snakes have been such a popular tattoo design for over a century is their ability to be combined with other tattoo symbols and the ease with which the tattoo artist can use the fluid and dynamic shape and form of the snake to emphasize the aesthetic lines of the human body.