What are the various of Yagnas (Fire rituals) performed in Hindu culture & what is their significance?
Non Indians and for people who are not exposed to Hindu culture
A Yajna is also called Homa, Havana - Literal meaning is sacrifices, often in fire. If you look at scriptures every dedicated work we do is comparable to Yajna. Every dedicated good deed covered , all of the thing we do for the self and society. Feeding people, Education, Meditation....
Yajna is some time mis-spelt and mis-pronounced as Yagna
The Big bang blast is the Yajna performed by the supreme power (purusha) by burnign himself to create (Rig veda Purushasukta)
In the context of this question Yajna is a fire sacrifices, where several ingredients are offered into fire, with different Mantras ( Chants). The Fire is a god who takes in the offering and ultimately see it reaches the gods.
When we chant we try to involve our mind,Ears, Mouth, Nose ( breathing ). This is to bring sync among our body and mind. it is done to burn any materialistic desires , get peace, clear obstacles etc.
The next level of chanting is Yajna, in which we involve eyes and body (touch) too. This will multiply the effect. When we wish and offer something into fire we are fully involved and get the feeling of accomplishment. When we deeply believe in the result with such an involvement, the theory of attraction starts working and we get the results.