Those who know Yoga or are already practicing Yoga must understand that actually all the Yoga postures were based on some natural phenomena. Like some form of animal or plant, there activities etc. Although most of the original Sanskrit names have now been transformed to new names (especially in English).
I am not saying that we should strictly follow the traditional names but what I mean to say is that those names were indicative of posture and how to attain it. Today one has to learn these postures from video or instructors who may or may not be quiet adept in Yoga.
Keeping the natural process of doing Yoga in mind will only help in developing our own insight about the posture by watching the nature and its phenomenons.
If we simply follow some exercises in routine which we think are from Yoga, we'll hardly discover all the benefits of Yoga. Understanding Yoga is vital to understand and discover the magic of Yoga. Explore Yoga from its traditions and then from our own views can only help us realize 'What is Yoga?' in its real sense.