In Hinduism and Buddhism, the third eye is a symbol of enlightenment (see moksha and nirvana). In the Indian tradition, it is referred to as the gyananakashu, "the eye of knowledge", which is the seat of the "teacher inside" or antar-guru. The third eye is the ajna chakra (sixth chakra) also known as brow chakra or brow center. This is commonly denoted in Indian and East Asian iconography with a dot, eye or mark on the forehead of deities or enlightened beings, such as Shiva, the Buddha, or any number of yogis, sages and bodhisattvas. This symbol is called the "Third Eye" or "Eye of Wisdom", or, in Buddhism, the urna. Many Hindus wear a tilaka between the eyebrows to represent the third eye. In the Upanishads, a human being is likened to a city with ten gates. Nine gates (eyes, nostrils, ears, mouth, urethra, anus) lead outside to the sensory world. The third eye is the tenth gate and leads to inner realms housing myriad spaces of consciousness.