Hinduism
The Avatar
The world 'Avatar' comes from the Sanskrit word avatāra, which means “descent”. In regards to Hinduism, the word 'Avatar' refers to "the incarnation of a deity in human or animal form to counteract some particular evil in the world." In the picture below, one can see a depiction of the Ten Avatars of Vishnu [1] [2].
The Ten Avatars of Vishnu
In The Last Airbender, the Avatar is one soul which gets reincarnated into a new human being upon death. The current Avatar can connect with the spirits of their past lives. The picture below from The Legend of Korra depicts dozens of spirits of past avatars, with Aang shown in the front.
All of the past Avatars, as shown in The Legend of Korra
The Seven Chakras
One of the common beliefs in Hinduism is that there are seven chakras, or places in the human body where energy is stored. The purpose of these chakras is to allow for spiritual, physical and psychological energies to connect with each other. Hindus can 'open' their chakras by practicing yoga in order to receive energy and/or enlightenment [3].
Depiction of the Seven Chakras and their corresponding places in the body
As shown in the image above, each chakra has a specific place in the body. For example, the Anahata chakra can be found near the heart [3].
In the The Last Airbender, Avatar Aang seeks the help of a guru in order to help him open his chakras, in order to allow him to access the 'Avatar State' at will, in order increase his power. In The Legend of Korra, Korra also ends up receiving cosmic energy, although in this case, the means for doing this were more ambigious. You can see the entire chakras clip from The Last Airbender in the YouTube video below. The descriptions of the chakras have been simplified, likely because the target demographic for the show is children. However, it is clear that the creators had Hinduism in mind when they wrote this portion of the show.
Aang receiving cosmic energy after clearing all seven of his chakras
Korra glancing at her cosmic self
"The Guru." Avatar: The Last Airbender. Nickelodeon. NICK, Los Angeles. 1 Dec. 2006. Television.
Articles/Books/Websites
1. The Editors of Encyclopædia Britannica "Avatar". 2 Feb. 2015. Web. 27 Feb. 2015. http://www.britannica.com/EBchecked/topic/45474/avatar
2. Partridge, Christopher H. “Introduction to World Religions”. Minneapolis, MN. Fortress Press, 2011.
3. Myss, Caroline. World Religions: Hinduism. 2010. Web. 03 Feb. 2015. http://www.myss.com/library/religions/hinduism/07_chakras.asp
Images
http://www.teefury.com/the-two-avatars
http://media.tumblr.com/tumblr_m8817c5KFh1r7jawq.png
http://spiceflair.com/wp-content/uploads/2011/12/The-Western-7-Chakras.jpg
http://i.ytimg.com/vi/hn1rAmh0VYI/maxresdefault.jpg