Aura is the electromagnetic field that surrounds us. Every person and every object in the universe has its own aura. The aura of a person, place or an object has layers of different colors and vibrations that keep changing according to our state of mind and emotions.
Our Aura is an external layer of our gross body that interacts with anyone or anything. Due to this very reason every person knowingly or unknowingly picks up on the vibrations of the others auras as they interact with one another. This goes to explain why some people's presence makes us feel extremely good while presence of others makes us uncomfortable.
Being first line of defense of our body against anything Aura is like the door to our house. Just like how a sturdier and more safeguarded door of the house keeps the house protected from any incident, in the same way a stronger and shielded aura protects the body from any impending diseases or external negative energies etc.
Aura can be badly affected in many occasions such as any trauma, mixing with crowds, any medical treatment etc.