Pretas, or “hungry ghosts,” are beings who are tormented by desire that can never be sated. They are often portrayed with tiny mouths and throats and the swollen bellies of the starving, meaning they can never consume enough to ease the suffering of their hungers
Pretas are described in many different Asian mythologies. In Buddhism, they are considered one of the six realms of cyclic existence (samsara), along with devas (gods), asuras (warring gods), humans, animals, and hell beings. Enlightenment can be defined as freeing oneself from these realms entirely.
Although the beings in them believe these realms are real, they are only subjective experiences created by mind. Each of the realms is characterized by a particular mental obscuration or klesha (see Buddhism by the Numbers). The preta realm is defined by attachment, and the truth that we can never end the suffering of unquenched desire, no matter how much we consume.
Because humans are not as solidly fixed in a particular mental state as other beings, our realm is defined by choice and the possibility of enlightenment. Moment by moment, we move from the bliss of the god realms to the anger of the hell realms to the stupidity of the animal realm. When breaks or gaps occur—spontaneously or cultivated in meditation—we glimpse the open, awakened mind that is always present but has been obscured by the fixations of the realms.