SAMSARA

Saṅsāra or Saṃsāra
                          (sanskrit: संसार; Telugu: సంసారం) literally meaning "continuous flow", is the cycle of birth, life, death, rebirth or reincarnation within  Hinduism, The word has its origins in the sramanic traditions of ancient India, and is today used in many modern Indian languages to refer to the physical world, or family, or the universe. In modern parlance, samsara refers to a place, set of objects and possessions, but originally, the word referred to a process of continuous pursuit or flow of life. In accordance with the literal meaning, the word should either refer to a continuous stream of consciousness, or the continuous but random drift of passions, desires, emotions, and experiences.      
                                          Life is not considered to begin with birth and end in death, but as a continuous existence in the present lifetime of the organism and extending beyond. The nature of the actions (karma) committed during the course of each lifetime, (good or ill) determines the future destiny of each being. Samsara is closely linked with the idea of rebirth (or reincarnation), but mainly refers to the condition of life, and the experience of life.
                               Samsara means "to flow on", to perpetually wander, to pass through states of existence.
The historical origins of a concept of a cycle of repeated reincarnation are obscure but the idea appears frequently in religious and philosophical texts in both ancient Greece and India during the middle of the first millennium BCE. In India the concept appears to have originated outside the mainstream Vedic religion in the heterodox Sramanic culture.  Reincarnation was adopted from this religious culture by Brahmin orthodoxy, and Brahmins first wrote down scriptures containing these ideas in the early Upanishads.
The Sanskrit word "Samsara" is the root for the Malay word "sengsara", which means suffering.

Cycle of rebirth
The concept of sansara is closely associated with the belief that one continues to be born and reborn in various realms in the form of a human, animal, or other being (depending on karma). In Hinuism maintains that, if one performs extremely evil karma, one can be reborn also as a plant or even as a rock, and similar tendencies can be found in Purāṇas, in the Bhagavadgītā, in the Manusmṛti and in similar texts. Nonetheless, most philosophic traditions of Hinduism ,maintain that plants and even more obviously rocks cannot be included in saṃsāra since they lack the possibility of experience (bhoga) and, hence, of karma.

 Saṅsāra in Hinduism

In Hinduism, it is avidya, or ignorance, of one's true self that leads to ego-consciousness of the body and the phenomenal world. This grounds one in kāma (desire) and the perpetual chain of karma and reincarnation. Through egoism and desire one creates the causes for future becoming. The state of illusion that gives rise to this is known as Maya.
Through ascetic practice one finally attains sanctity and liberation (moksha or mukti) - the equivalent of salvation in Indian religions.
Broadly speaking, the holy life (brahmacarya) which leads to liberation is a path of self-purification by which the effects of sins are released.
The Hindu Yoga traditions hold various beliefs. Moksha may be achieved by love of Ishwar/God (see bhakti movement, see Mirabai), by psycho-physical meditation (Raja Yoga), by discrimination of what is real and unreal through intense contemplation (Jnana Yoga), and through Karma Yoga, the path of selfless action that subverts the ego and enforces understanding of the unity of all.
The Rig Vedic, Yajur Vedic and Atharva Vedic Upanishads like Aiteraya Upanishad, Taittiriya Upanishad, Swetaswatara Upanishad, Mundaka Upanishad etc. contains the most ancient ideas on Reincarnation of soul.As confirmed by latest research in the field of archeology and Astronomy, Vedas were older than 2600 BC which takes it far earlier than all other religious texts. Hence, based on this, the earliest known texts to have spoken about karma, sansara and Moksha or Mukti, are the Vedas and other Dharmic Texts. (Dharmic Texts stands for the Vedas, Ithihasas and Puranas). The Vedas describe Karma as the result of enjoying the sensory pleasures of this material universe.