Yoga Nidra also known as Yogic Sleep is a immensely powerful meditation technique. It is a state of consciousness between waking and sleeping. 

Practicing Yoga Nidra slows the wavelengths in your mind as you enter a sleep-like state. The experience often starts with sensing the body and mindfully breathing to trigger the relaxation response in your body, it also trains your mind and body for this relaxation process so you can reach a deeper state of sleep, the entry point to the subconcious. 

There are many benefits to practice Yoga Nidra, it helps release tension & pain; allow you to connect with yourself; improves your sleep and reduce insomnia; detaching yourself from your thoughts and many more.