The significance of Adiyogi is he provided methods to evolve human consciousness that are relevant for all times.  

Absolute stillness and ultimate movement are the nature of Shiva - and that is the Way.

The spine of knowledge that the Adiyogi created is the source of almost everything you can call spiritual on the planet.

Mahashivratri is the great night of Shiva. If you maintain wakefulness and some sense of awareness on this sacred night, it shall bring tremendous wellbeing to your life.