The symbol of AUM consists of three curves (1, 2, and 3), one semicircle (4), and a dot.
The large lower Curve 1 symbolizes the waking state – jagrat, in this state the consciousness is turned outwards through the gates of the senses.
The larger size indicates that this is the most common and major state of the human consciousness.
Curve 2 denotes the state of deep sleep- sushupti or the unconscious state. This is a state where the sleeper desires nothing nor beholds any dream.
Curve 3 – which lies between deep sleep and the waking state, signifies the dream state – swapna.
In this state the consciousness of the individual is turned inwards, and the dreaming self beholds an enthralling view of the world behind the lids of the eyes.
These three curves therefore represent the entire physical phenomenon.
The dot signifies the fourth state of consciousness, known in Sanskrit as turiya. It signifies the coming to rest of all differentiated, relative existence. This quiet, peaceful and blissful state is the ultimate goal of all spiritual activity.
The semi circle (4) symbolizes maya and separates the dot from the other three curves. Thus it is the illusion of maya that prevents us from the realization of this highest state of bliss. The semi circle is open at the top, and does not touch the dot.
This means that this highest state is not affected by maya. Maya only affects the manifested phenomenon. This effect is that of preventing the seeker from reaching his ultimate goal, the realization of the One, all-pervading, unmanifest, Absolute principle.