We are going to discuss about Meditation based on "Pantajali Yoga Sutra (Ashtanga Yoga)". In his sutras the "Sage Patanjali" has explained 8 limbs of yoga (Ashtanga Yoga). Those are :- Yama, Niyama, Asana, Pranayama, Pratyahara, Dharana, and Dhyan Samadhi. The initial four stage are the basic stages which help the person to attain "Sthiram" (stability of mind) which is the prior necessity for practicing the further stages of meditation. According to him meditation (Dhyan) means -
"Full concentration of the mind focused on one of those experiences"
In simple terms the spontaneous concentration of the mind on the object is Meditation.