NDE — An NDE is a “near-death experience”, one of several names for an experience with a set of common characteristics, beginning with a separation of the person’s consciousness from their physical body (usually the result of a severe health crisis), but also including some or all of the following:
the mind functioning more clearly and rapidly than usual
the sensation of being drawn into a tunnel or darkness
a brilliant light, sometimes at the end of the tunnel, usually experienced as a being of light, love, and acceptance
a sense of peace, well-being, and/or unconditional love
a sense of having access to unlimited knowledge
a "life review" or recall of important events in the past
a preview of future events yet to come
encounters with deceased loved ones, or other beings generally identified as religious figures
One of the frequent things said by those who have had such an experience is that time and space are not anything like how they are experienced in the physical world. Despite that, most NDErs say that their experience of that world is “more real” that their experience in the physical world, making an NDE very different from a dream or hallucination.
OBE — An OBE is an “out-of-body experience”. It is similar to an NDE, and may actually be the first stage of an NDE. In an OBE, the person’s consciousness becomes separated from their physical body. Generally their consciousness remains near their physical body, especially in a situation where the OBE is initiated by a severe health crisis. Many having an OBE described their consciousness as looking down on their body from a short distance above, as if it had floated into the corner of the room near the ceiling. No two OBEs are exactly alike, but most have similar characteristics.
Life Review — A life review is a common characteristic of an NDE. You have certainly heard the idea that a person nearing death has “their whole life flash before their eyes”. This would certainly be one way to describe a life review. During an NDE, the individual is often met by spiritual beings, and may, at that moment, see or even re-experience all or most of the events of their life. The way NDEers have described the details of a life review varies widely. This may be because the experience of each individual is different, and not merely because it is difficult to put such an unearthly experience into words.