Nataraja Shiva, The Lord of the Dance

Shiva's association with dance and art is well known. He is also known as the Lord of Dance (Nataraja). Many statues of him are available in this form. In the religious texts he is also described as the one who performs a particular type of dance called tandava, whenever he is disturbed or angry (tandavamurthi) or when the time for the end of the world comes. When he is in a peaceful mode, he said to perform more pleasant dance known as Lasya, displaying his feminine side. Both the dance forms denote the creative and destructive aspects of our creation and Siva being the Lord of all, according the Saivism, He performs actions according to the needs of the occasion.

Characteristics

The dance form of Nataraja is known as ananda tandava or the dance of bliss. He is usually shown as performing it under an arch of flame, which signifies his symbolic association with Agni the fire God and the act of destruction. A cobra uncoils from his lower right forearm, and the crescent moon and a skull are on his crest.

The upper right hand holds a small, hourglass shaped drum (called ḍamaru in Sanskrit). It is held with a specific hand gesture (mudra) called ḍamaru-hasta . The drum symbolizes sound, which in turn stands for life and creation. The upper left hand contains Agni or fire, which signifies destruction. Thus both the right and left hands show the opposing aspects of life, namely creation and destruction, under the control of one Master, namely Shiva. The lower right hand is held in abhaya mudra, suggesting divine assurance of protection from both evil and ignorance to those who follow the righteousness of dharma. The lower left hand points towards the raised foot which signifies upliftment and liberation. The Lord of the Dance places his left feet upon a dwarf who is described in the scriptures as  the demon Apasmara, who symbolizes ignorance or ego (anava). The right leg is lifted in the air, suggestive of the particular form of dance in which the Lord is engaged, which is known as tandava. The surrounding flames represent the manifest Universe. Also, the circle of fire/flames symbolizes the cycle of transmigration/suffering the ego goes through(endless births and rebirths, before attaining salvation). The snake swirling around his waist is kundalini, the Shakti or divine force thought to reside within everything.
The stoic face of Shiva represents his neutrality, thus being in balance.

Significance

Although the dance of Nataraja is popularly associated with destruction, it is actually the dance life, creation and destruction. It is symbolizes movement or dynamism (chaitanya) which is inherent in all living forms and through whcih life expresses itself in various forms. It also stands for divine activity which is responsible for everything that happens in the manifest worlds. God being the Lord of the universe, manifests the worlds according to His will, enjoys His creation while it lasts and then destroys them in the end. The fact that Shiva places his feet upon ignorance, denotes the fact that the dance is not a destructive act in the real sense of the word, but an act of liberation. God liberates souls by destroying their ignorance. He also sets them free from the cycle of births and deaths at the end of each timecycle, whcih lasts for millenniums.