An aura is an energy field that surrounds the body and contains electro magnetic energy amongst other ethereal properties, when seen with the naked it eye it can look like a white misty outline and is more noticeable around the head and shoulders. Not only do we have an aura but every material object has an aura, animals, trees, rocks etc. Auras can vary in texture, quality, and feel in relation to the vibrational nature of each individual and aura is constantly changing from moment to moment as we change and develop.
By looking at a persons aura we can see many things about that person, their state of health, mood, energy levels and even what they are thinking via thought forms. Thought forms are created when we think and are expanded out into the aura and can sometimes be seen by looking at the aura, from my experience of looking at auras and seeing thought forms, thought forms tend to manifest themselves as images rather than words, for example lets say someone was thinking about a drink then you may see an image of a cup appear, this can also be the same if the person is thirsty, these images are also a white misty colour. With practice you can even tell if someone is lying to you as their thought forms won't be consistent with what they are telling you. We cannot fake the aura, it shows our true colours and intentions, hence the saying "showing your true colours".
Our auras can affect us and we can affect are auras, if our aura is imbalanced in some way then this can effect our mood, health energy levels etc and things we do or certain coloured clothes we wear can affect our auras, so by looking at auras we can discover and balance out any imbalances that our auras have.
Colours can also be seen within the aura although this is rare and those who claim to see bright vivid colours often sense or see them clairvoyantly in their mind and not physically, if colours are seen physically with the naked eye they will appear very pale sometimes to the point where it's hard to distinguish what colour is actually there, unless you can sense or see the colour within your mind. Colours do have basic meanings which can be found on the colours page but each person will have their own personal meaning to colours. Auras can have different shapes and sizes, this is dependent on a lot of things as mentioned above, although the shapes themselves don't really have any particular meaning, it's just the way the aura is and everyone's aura is different.
Another point to cover here is Aura Photography, don't be fooled by it, aura cameras are built to project artificial light directly onto the film while taking the picture, thus giving an aura affect and are totally fake photos, the lights are activated by measuring skin resistance which has nothing to do with auras what so ever. Quite often when having your aura photo taken you will be seated in a chair, the chairs have sensors on them that measure the skin resistance, it's the same principle that lie detectors use. You can see similar things at fair grounds and gambling arcades, these are machines that give you psychic readings and an aura photo, you have to put your hand onto a metal plate (the skin resistance sensor) and you get an aura photo along with your reading. There are even simple mobile phones apps these days, that do similar things, but without the need for sensors, they just overlay random colours over the picture.