What do Buddhists believe about the realms of existence?
Many Buddhists such as Tibetan, believe that there are Six Realms of Existence into which we can be reborn - as shown in the Bhavachakra.
Devas or Gods in a Heavenly Realm
Asuras or Jealous Gods in the Titan Realm o Manushuras in the Human Realm
Tiryakas in the Animal Realm
Pretas in the Hungry Ghosts Realm
Narakas in the Hell Realm
Whilst the Gods live a life of pleasure, it is not the best realm for Buddhists as it still involves ignorance. The optimum realm for reaching enlightenment is the human realm as all the others are distracted by too much pleasure or suffering. Many Buddhists think these Realms are symbolic of mental states.
Continued rebirth necessarily involves dukkha, and therefore Buddhists want to escape it by reaching enlightenment and Nirvana.