Karma and samsara

Karma translates literally as action, work, or deed, and can be described as the "moral law of cause and effect". According to the Upanishads an individual, known as the jiva-atma, develops sanskaras (impressions) from actions, whether physical or mental. The linga sharira, a body more subtle than the physical one but less subtle than the soul, retains impressions, carrying them over into the next life, establishing a unique trajectory for the individual, Thus, the concept of a universal, neutral, and never-failing karma intrinsically relates to reincarnation as well as to one's personality, characteristics, and family. Karma binds together the notions of free will and destiny.

This cycle of action, reaction, birth, death and rebirth is a continuum called samsara. The notion of reincarnation and karma is a strong premise in Hindu thought. The Bhagavad Gita states:

Samsara provides ephemeral pleasures, which lead people to desire rebirth so as to enjoy the pleasures of a perishable body. However, escaping the world of samsara through moksha is believed to ensure lasting happiness and peace. It is thought that after several reincarnations, an atman eventually seeks unity with the cosmic spirit (Brahman/Paramatman).

The ultimate goal of life, referred to as moksha, nirvana or samadhi, is understood in several different ways: as the realization of one's union with God; as the realization of one's eternal relationship with God; realization of the unity of all existence; perfect unselfishness and knowledge of the Self; as the attainment of perfect mental peace; and as detachment from worldly desires. Such realization liberates one from samsara and ends the cycle of rebirth. Due to belief in the indestructibility of the soul, death is deemed insignificant with respect to the cosmic self. Thence, a person who has no desire or ambition left and no responsibilities remaining in life or one affected by a terminal disease may embrace death by Prayopavesa.

The exact conceptualization of moksha differs among the various Hindu schools of thought. For example, Advaita Vedanta holds that after attaining moksha an atman no longer identifies itself with an individual but as identical with Brahman in all respects. The followers of Dvaita (dualistic) schools identify themselves as part of Brahman, and after attaining moksha expect to spend eternity in a loka (heaven), in the company of their chosen form of Ishvara. Thus, it is said that the followers of dvaita wish to "taste sugar", while the followers of Advaita wish to "become sugar".

Source : Wikipedia