In Hinduism, Yajna (Devanagari यज्ञ IAST '; also anglicized as Yagna or Yagya) is a Vedic ritual of sacrifice (Monier-Williams gives the meanings "worship, prayer, praise; offering, oblation, sacrifice"), performed to please the Devas, or sometimes to the Supreme Spirit Brahman. It involves pouring oblations into the divine Agni (the sacrificial fire). Everything that is offered in the divine Agni is believed to reach the Devas. A yajna is typically performed by a hotar, with a number of additional priests playing a supporting role, chanting Vedic verses. Often there will be a fire in the centre of the stage and items are offered into the fire. Among the items offered as ahuti in the Yajna' include many coconuts, large quantities of ghee, sandalwood shavings and even quantities of clothing. A yajna can go on for several hours, typically with a large number of people in attendance. Yajna ,where milk products (ghee or yogurt), fruits, flowers, cloth, and money are offered, is also termed homa or havan''. A typical Hindu marriage essentially consists of a yajna, because the fire deity Agni is supposed to be the witness of all pious marriages. Brahmins and certain other castes receive a yagnopavitham at their Upanayanam. The yagnopavitham symbolizes the right of the individual to carry out yagnas or homams. The mode of temple worship is termed agamic, while communication to divinity through the fire god, Agni, is considered Vedic. Temples of today are generally a combination of both Vedic and Agamic rituals.
Hindu tradition has the Pancha Mahayajnas ("Five Great Yajnas", Taittiriya Aranyaka 2.10) namely:
Those yajnas explicitly described in the Vedas are known as Shrauta yajnas. The Vedas describe 400 * Yajnas. In the category of nitya-karma there are 21 sacrifices. There is no compulsion with regard to the rest of the 400 Yajnas. But the 21, included in the forty samskaras, are required to be performed at least once in a lifetime of a Dvija. These are divided into groups of seven - paaka-yajnas, havir-yajnas, and soma-yajnas.
Pakayajnas are minor sacrifices and are performed at home. On every Prathama (first day of the lunar fortnight), a pakayajna and a haviryajna have to be performed in the grhyagni and srautagni respectively. The first is called sthalipaka. "Sthali" is the pot in which rice is cooked and it must be placed on the aupasana fire and the rice called "caru" cooked in it must be offered in the same fire.
The haviryajnas are more elaborate, though not so large in scale as the somayajnas. The haviryajna performed on every Prathama is "darsa-purna-isti", "darsa" meaning the new moon and "purna" the full moon. So the "istis" or sacrifices conducted on the day following the new moon and the full moon (the two Prathamas) are together given the name of darsa-purna-isti. The two rituals are also referred to merely as "isti". This is the prakrti (archetype) for haviryajnas. The first four haviryajnas - adhana, agnihotra, darsa-purna-masa and agrayana - are performed at home. The last three haviryajnas - caturmasya, nirudhapasubandha and sautramani - are performed in a yagasala.
The name somayajna is derived from the fact that the essence of the Soma plant, said to be relished by the celestials, is made as an oblation. For soma sacrifices "agnistoma" is the prakrti, the word "stoma" also meaning a sacrifice. Apart from this, animals are also sacrificed. Even so the Saman is sung. In such soma sacrifices there is the full complement of priests - the hota, the adhvaryu, the udgata and the brahma. Each priest is assisted by three others. So in all there are sixteen priests in a soma sacrifice. Agnistoma which is the first of the seven somayajnas is the prakrti (archetype) and the other six are its vikrti. These six are: atyagnistoma, uktya, sodasi, vajapeya, atiratra and aptoryama. Vajapeya is regarded as particularly important. When its yajamana (sacrificer) comes after having had his ritual bath (avabhrtha snana) at the conclusion of the sacrifice, the king himself holds up a white umbrella for him. "Vaja" means rice (food) and "peya" means a drink. As the name suggests, the vajapeya sacrifice is believed to bring in a bountiful crop and plentiful water. The name is appropriate in another sense also. This sacrifice consists of soma-rasa homa, pasu-homa (23 animals) and anna - or vaja-homa. The sacrificer is "bathed" in the rice that is left over. Since the rice is "poured over" him like water the term "vajapeya" is apt. *
See Also: Shrauta
Hindu Worship | Religious behaviour and experience | Hindu traditions | Yajna