Your actual physical body is only a small  part of your   true self .
What you see is not   all you get.  The human body is   not just the
blood and bones we perceive on the  physical plane. We are made of
energy that  permeates every layer of our being,  it is us. What we
know as the physical body is just energy that is vibrating more
slowly than the energy that is beyond our  standard perception. The aura
or energy   field is usually invisible to the physical vision but most
people can learn to  perceive it in one way or another with  practice.
The aura is densest close to the   body  and becomes finer moving away
from it . Most  human Auras extend from 1   to five feet out around the
body. though in more spiritually developed  individuals it is  said that
they can extend outward up   to 50 feet from the body. and even further
in some cases. (actually anyone can do this).

    The Aura and energy body has layers and   energetic structures and
channels and organs within it. Trauma and emotional disturbance can
create  blocks and other damage   in your energy body, if this damage
is not repaired and continues to   occur over  a time then the outward
manifestation of this is disease  or mental or emotional disruption.
The aura is the field of energy that permeates   the body and extends out from it from two to   five feet in most people.
    Some common names for the aura  layers from the inner most dense to the outer finer    or higher vibration layer are 1. etheric 2. emotional 3.  mental 4. causal 5.   etheric template 6. intuitive 7. cosmic.
These names are by no means complete or  definitive  and several of the individual layers and the  whole system is /are often called the astral    body.  
 There are many more layers of the energy body  or aura than the seven most often listed I   have been  told there are actually 32 and also that there are 89 but I am not in a position to count them. These aura  layers are not segregated in the way the use of the word layer  might seem to imply.

Each layer of the  aura interpenetrates the others and begins at our    center. The vibration of each  level becomes finer and  higher as we go from the inside out.  The aura levels do not correspond directly to the esoteric planes  which is a whole other incredibly complex and   obscure area of study.

We are only part of a vast interconnected energy universe (which is said to be both vibratory and crystalline in nature) . We will focus on the individual human aura now. Plants  and animals and even inanimate objects also have  auras but they differ in structure in varying degrees  from the Human aura at least as we can perceive   them.
 

    There has been considerable confusion and  variation about the names given each     of  the seven most well known aura levels. These descriptions are  of common ways the aura is  perceived but are by no
means the only or definitive description.
 When trying to see the   aura, please remember that this is subtle   energy and is not a light show.  While aura   viewing is   not a strong ability of mine I discovered that I had  been seeing them fairly often  but had been
dismissing them as optical effects or heat waves and such, though I am better able to feel the energy    layers than to  see them. The aura changes constantly  it may have a predominant color in the emotional  and causal layers. The way the aura is perceived can  vary greatly from person to person so  remarks about  the layers
are based on a general consensus but are    by no means absolute. Size also varies greatly largely   depending on the energy level of the person and the  way  they use that particular part of themselves.

Stress, trauma and emotional pain can show as  distortions and blocks in the aura long before they manifest as illness in the physical plane. Each layer is related to the chakra of the same  number.
From the inside outward from the body or nearest the    physical skin though all layers also  penetrate the  body.

1. Etheric: lower astral, root chakra, a bluish or   grayish layer that extends an inch or two  out from the body. Most associated with the physical body is the easiest to see . some  people are able to see the
etheric outlines of the internal organs . Some people see a light   blue on dark blue grid. Survival issues, the physical body function and physical sensation of  pain, pleasure, automatic functions etc.

2. Emotional: Sacral Chakra, the emotional aspects of our lives and being.
soft multi colored clouds of light visible from one to six inches out This is the layer most often  described by aura readers it will show dark spots or    cloudy area and stagnant areas where  emotional blocks and pain exist
.

3. Mental: golden grid ,Solar Plexus Chakra, the mental body reflects the thought processes, intellect  , linear  thinking. Personal power and will.

  These three bodies are the lower astral and  together are said to make up the personality .   These energy bodies are said to begin to be created at conception and   dissolve at death.

4. Causal:, Higher Astral, Buddic ,Heart chakra, multi colored clouds ,associated with the   heart and love .This connects the lower three levels/layers  with the higher three . Virtually all   healing energy is said to come through or be moderated by this layer it is the  layer of love both specific and universal,  and the first  of the spiritual
layers.

5. Atmic:  (Etheric template) bliss, throat chakra, the higher aspects of the will more connection with the divine will, speech and communication, listening, taking responsibility  for ones own actions seen by some as a blue grid
light  ball around the body  and extending about   2 and a half feet out from the body. it has been very  rare for people to be really aware of this layer but when balanced and active it can promote a bliss and a
feeling of being moved   by the divine. It is becoming more open in people at  this time. Power of word, manifesting.

   6. Intuitive: (monadic) ketheric template, Brow    chakra, multicolored (iridescent) threads of light,  spiritual communication Divine Love, Nurturing    awareness of oneself as an aspect of what is  called, By
some, God, Love of all life and union with the all.

7. Cosmic: universal, ketheric, ball of golden or brilliant white light threads, Crown chakra, Higher  mind, connection with the divine and spiritual information and the integration of the   spiritual and
physical aspects of being.