Avatāra—literally means "one who descends." A partially or fully empowered incarnation of the Lord who descends from the spiritual sky to the material universe with a particular mission described in scriptures; When Kṛṣṇa descends from the world of spirit into the world of matter, His appearance here is called avatāra. The Sanskrit term avatāra (one who descends) is often rendered into English as incarnation. It is wrong, however, to think that Kṛṣṇa incarnates in a body made of physical elements. The Seventh and Eighth Chapters of Bhagavad-gītā distinguish at length between the material nature (apara-prakṛti), visible as the temporary substances of earth, water, fire, air and ethereal space, and God's own spiritual nature (para-prakṛti), which is invisible (avyakta), eternal (sanātana) and infallible (akṣara). When the Lord descends, by His mercy the invisible becomes visible. As He Himself states in Bg. 4.6, I descend by My own nature, appearing in My form of spiritual energy (prakṛtiṁ svām adhiṣṭhāya sambhavāmy ātma-māyayā). In Bg. 4.9 He declares, janma karma ca me divyam, My appearance and activities are divine. God has many avatāras. But of all of them, that form described in Bg. 11.50 as the most beautiful (saumya-vapu) is His own original form (svakaṁ rūpam). This is the eternal form of Śrī Kṛṣṇa, the all-charming lotus-eyed youth whose body is the shape of spiritual ecstasy. SB 1.3.28 confirms that Kṛṣṇa is the original form of Viṣṇu: ete cāṁśa-kalāḥ puṁsaḥ kṛṣṇas tu bhagavān svayam indrāri-vyākulaṁ lokaṁ mṛḍayanti yuge yuge, which means, All of the incarnations of Viṣṇu listed in the scriptures are expansions of the Lord. Lord Śrī Kṛṣṇa is the original Personality of Godhead. All avatāras appear in the world whenever there is a disturbance created by the atheists. The Lord incarnates to protect the theists. The Śrīmad-Bhāgavatam also provides us with the authorized list of scheduled incarnations of Godhead, of whom the Daśāvatāra (ten avatāras) are particularly celebrated. The ten are 1) Matsya (the Lord's form of a gigantic golden fish), 2) Kūrma (the turtle), 3) Varāha (the boar), 4) Śrī Nṛsiṁha (the half-man, half-lion form), 5) Paraśurāma (the hermit who wields an ax), 6) Vāmana (the small brāhmaṇa boy), 7) Śrī Rāmacandra (the Lord of Ayodhya), 8) Śrī Baladeva (Lord Kṛṣṇa's brother), 9) Buddha (the sage who cheated the atheists), and 10) Kalki (who will depopulate the world of all degraded, sinful men at the end of the present Age of Kali). There are two broad categories of avatāras. Some, like Śrī Kṛṣṇa, Śrī Rāma and Śrī Nṛsiṁha, are Viṣṇu-tattva, i.e. direct forms of God Himself, the source of all power. Others are individual souls (jīva-tattva) who are empowered by the Lord in one or more of the following seven ways: with knowledge, devotion, creative ability, personal service to God, rulership over the material world, power to support planets, or power to destroy rogues and miscreants. This second category of avatāra is called śaktyāveśa. Included herein are Buddha, Christ and Muhammed. The Māyāvādīs think that form necessarily means limitation. God is omnipresent, unlimited and therefore formless, they argue. When He reveals His avatāra form within this world, that form, being limited in presence to a particular place and time, cannot be the real God. It is only an indication of God. But the fact is that it is not God's form that is limited. It is only the Māyāvādīs' conception of form that is limited, because that conception is grossly physical. God's form is of the nature of supreme consciousness. Being spiritual, it is called sūkṣma, most subtle. There is no contradiction between the omnipresence of something subtle and its having form. The most subtle material phenomena we can perceive is sound. Sound may be formless (as noise) or it may have form (as music). Because sound is subtle, its having form does not affect its ability to pervade a huge building. Similarly, God's having form does not affect His ability to pervade the entire universe. Since God's form is finer than the finest material subtlety, it is completely inappropriate for Māyāvādīs to compare His form to gross hunks of matter. Because they believe God's form is grossly physical, Māyāvādīs often argue that any and all embodied creatures may be termed avatāras. Any number of living gods are being proclaimed within India and other parts of the world today. Some of these gods are mystics, some are charismatics, some are politicians, and some are sexual athletes. But none of them are authorized by the Vedic scriptures. They represent only the mistaken Māyāvādī idea that the one formless unlimited Truth appears in endless gross, physical human incarnations, and that you and me and I and he are therefore all together God. And since each god has a different idea of what dharma is, the final truth, according to Māyāvāda philosophy, is that the paths of all gods lead to the same goal. This idea is as unenlightened as it is impractical. When ordinary people proclaim themselves to be God, and that whatever they are doing is Vedic dharma, that is called dharmasya glāniḥ, a disturbance to eternal religious principles. Therefore Kṛṣṇa came again, 500 years ago, as the Golden Avatāra, Caitanya Mahāprabhu. He established the yuga-dharma, the correct form of sanātana-dharma for our time (saṅkīrtana). Lord Caitanya's appearance was predicted in SB 11.5.32: In this Age of Kali, people who are endowed with sufficient intelligence will worship the Lord, who is accompanied by His associates, by congregational chanting of the holy names of God. See Caitanya Mahāprabhu, Kṛṣṇa.