There are six Buddhist realms of samsaric existence. Buddhists believe that the cycle of a person’s life is perpetrated by ignorance, greed, pride, anger and jealousy.
Considered as the highest among the six realms of existence, it is characterized by the attributes of the Buddha. Enlightenment is considered to be easily attained in this realm; and everything sparkles with love and light.
Demi-god Realm (Jealous God Realm)
The second highest realm of existence is called the Demi-god realm, or the Jealous God Realm. It is believed to be the realm of Titans, Asuras, and is marked by jealousy and paranoia. Those born into this realm, though blessed with a high birth, are exceedingly jealous of the God realm and of each other. They are believed to spend most of their time fighting among themselves to compete.
Being born into the human realm is considered to be a very rare occurrence. It is only in the human realm in which liberation from all the six states is possible. The human realm is characterized by doubt and inquisitiveness and the longing for something better.
The Animal Realm is characterized by ignorance which is equivalent to having a mind similar to that of an animal. The animal realm is nothing but suffering where there is no way in obtaining knowledge and taking steps towards enlightenment.
Preta Realm (Hungry Ghost Realm)
This realm is characterized by craving/desire. It is believed that in the hungry ghost or preta realm, the inhabitants suffer from a greed that can never be satisfied. They have huge stomachs but tiny mouths, food and water is very scarce and when a preta sees food or water they are so delusional that they believe they are seeing blood, bile and other disgusting things of that nature. And even if a preta finds food or water and is able to consume it, it burns their throat and stomach like fire.
The lowest among the realms of existence is the hell realm. Buddhists believe that there are about 136 hells which are divided into “hot hells” and “cold hells”. The hell realms are looked upon as journey full of suffering; one born into this realm must not only endure suffering in their respective hell but also pass through each of lesser hells. This journey is supposed to take years to complete. In the course of which, even the Dharma is forgotten and even if it was remembered, the anguish is such that it makes practice impossible. The hell realm is characterized by acute aggression.
Buddhists believe that each person is reborn in accordance with their respective actions (Karma) in their previous lives.