"Astral" and "etheric"
The expression "astral projection" came to be used in two different ways. For the Golden Dawn and some Theosophists it retained the classical and medieval philosophers' meaning of journeying to other worlds, heavens, hells, the astrological spheres and other imaginal landscapes, but outside these circles the term was increasingly applied to non-physical travel around the physical world.
Though this usage continues to be widespread, the term, "etheric travel", used by some later Theosophists, offers a useful distinction. Some experients say they visit different times and/or places: "etheric", then, is used to represent the sense of being "out of the body" in the physical world, whereas "astral" may connote some alteration in time-perception. Robert Monroe describes the former type of projection as "Locale I" or the "Here-Now", involving people and places that actually exist: Robert Bruce calls it the "Real Time Zone" (RTZ) and describes it as the non-physical dimension-level closest to the physical. This etheric body is usually, though not always, invisible but is often perceived by the experient as connected to the physical body during separation by a “silver cord”. Some link "falling" dreams with projection.
According to Max Heindel, the etheric "double" serves as a medium between the astral and physical realms. In his system the ether, also called prana, is the "vital force" that empowers the physical forms to change. From his descriptions it can be inferred that, to him, when one views the physical during an out-of-body experience, one is not technically "in" the astral realm at all.
Other experients may describe a domain that has no parallel to any known physical setting. Environments may be populated or unpopulated, artificial, natural or abstract, and the experience may be beatific, horrific or neutral. A common Theosophical belief is that one may access a compendium of mystical knowledge called the Akashic records. In many accounts the experiencer correlates the astral world with the world of dreams. Some even report seeing other dreamers enacting dream scenarios unaware of their wider environment.
The astral environment may also be divided into levels or sub-planes by theorists, but there are many different views in various traditions concerning the overall structure of the astral planes: they may include heavens and hells and other after-death spheres, transcendent environments or other less-easily characterized states.
Read more about this topic: Astral Projection