Millions of people all over the world practice "yoga" every day. They practice different styles of yoga - some akin to a gentle stretch and others, like the Ashtanga method, that are so intense that it is a sweaty workout. People practice yoga for various reasons - to maintain general health, to have toned bodies, to calm the mind, to relax tense muscles and for spiritual reasons. Whatever reason people practice it for, it is good to take a lighter look at the practice and understand the original intent of the practice so that we are not beleaguered when our bodies don't cooperate to meet the various contortions that these poses demand.

1) The images that the terms Yogi and Yogini would conjure in one's mind 

Then

Images of people with subtle powers over their body, gained through deep meditation

Now

Images of people contorting their bodies into difficult positions

So how did Asanas, which are a tiny portion of the yoga practice, come to be known by the name "Yoga" ? (See this article)

2) Wishing to grow old and wishing to feel young

3) Diet 

4) Yoga and Yogas 

Then

There was only Yoga.

Now

There are various kinds of yoga practices with fanciful names and whatmore, people try to copyright sequence of poses that were handed to them from thousands of years ago