From the Ancient Period the Guru Parampara of Guru Tradition protect us from our ignorance and lead us towards our enlightenment. In several traditions and cultures the Role of Guru is very significant.
There will be a famous saying on Guru:
Gurur Brahma Gurur Vishnu
Gurur Devo Maheswara
Gurur Sakshaat Param Brahma
Tasmai Shri Gurave Namaha
The Enlightened Guru is no other than Brahmaa the Creator, Vishnu the Preserver, and Shiva the Destroyer.
Guru is Truly The Almighty Brahmaan, our salutations to Him; the Divine Spiritual Master.
I prepared these Guru Purnima drawings in powerpoint.