After practicing pranayama (control of vital energy) and pratyahara (control of senses) followed by Dharana, ie the focusing of the mind on one point. Dharana is concentration.
Attention is dissipated as the mind tends to wander, our goal is to harness focus the rays of thought on one point.
The concentration of the mind (and the direction to) on an object inside or outside as well as the ability to remain adhered to it, has resulted in the development of stability of mind to achieve release from the shackles of objects.
Dharana means to accept anyone to stay engrossed in the object of meditation for at least 12 seconds.
The focus point can be the flame of a candle, a dot on the wall, a sound, a word, an image, etc ....
It is an important preparation for meditation.