When I first started doing yoga, like many people in the western world, I was drawn to the physical practice. The way it calmed my mind and worked my body at the same time, a kind of moving meditation, offered respite from the stress, anxiety and problems in the rest of my life and helped me to feel grounded in my body. However, though it was this physical practice that originally brought me and many western practioners to the mat, the physical practice of yoga is only one part of of yoga.
Yoga is made up of 8 Limbs:
Yamas - Moral principles that guide interactions with others
Niyamas - Moral principles that guide interactions with yourself
Asana - Physical postures of yoga (to prepare the body for meditation)
Pranayama - Conscious control of the breath (to prepare for meditation)
Pratyahara - Withdrawing from the external senses to focus inward for meditation
Dharana - Focused meditation with intense concentration on a specific thing
Dyhana - Peaceful, meditative awareness without judgement or attachment
Samadhi - A state of bliss, liberation and union of body and mind, with pure awareness that all is one
While samadhi is the ultimate objective of a yogic life, physical practice, breath practice, and meditation are intended as steps along the path to support our journey to there. What we think of as yoga in the west is essentially modern postural practice (asana), though many teachers incorporate breathwork (pranayama) and meditation as well. We can practice the first 5 limbs through a principled life, relationship with ourselves, physical practice, control of the breath and meditation, but the final three limbs are states of being that one reaches through consistent practice.
Exploring the other limbs of yoga allows you to explore and live your values, known yourself on a deeper level, and find a place of inner calm, connection, and peace. If you want to explore yoga more, there are literally thousands of articles, books, podcasts and youtube talks about it. Check out some of my favorites on the Diversity and Roots of Yoga pages.