Every individual has desires to acquire things which help individual to accomplish. These accomplishments are known as Purusharthas.
Dharma, artha, kama and moksha are the four purusharthas.
Accomplishing these four values which are known as purusharthas is the aim of every individual.
Ashtanga yoga is a very good disciplined and a systematic way to practice yoga.
Yama, niyama, asana, pranayama, pratyahara, dharana, dhyana and samadhi are the eight limbs of ashtanga yoga.