Guru Purnima, Sadguru,Guru Shishya Parampara

Blessings on the day of Guru Purnima !
It is not to be mistaken for 'Plain Teacher's Day' even though teacher's day is no less!To understand Guru or rather 'Sadguru' we must acknowledge the fact that ,we cannot select a Sadguru or make Anyone. We are the source of 'lesser' knowledge and achievement.He/She is the one who will choose from amongst us, who is worthy of being his 'Shishya' or 'Chela'.
Let us first find out what Guru Purnima is:
http://en.wikipedia.org/wiki/Guru_Purnima
It is the full moon day in the month of Aashaad.
Sadguru is the one whom we remember and honour....
"Vihangam Yoga Says:[1]:
There is a lot of darkness in this world - the darkness of evils , the darkness of illiteracy about the truth of oneself, the darkness of maya and nature that forbids you from the truth of this world.The one who takes you away from this darkness of nature into a state of light that shows who you are , where are you from , whom actually you belong to, and what is the actual aim of having this human form is called the Satguru.Satguru is the one who has seen the God and who is capable enough to show it to his disciples. "
http://en.wikipedia.org/wiki/Satguru
This Guru- Shishya( paramapra) tradition has it's roots long back in history ...
"Often a guru will assert that he or she is capable of leading a shishya directly to the highest possible state of spirituality or consciousness, sometimes referred to within Hinduism as moksha. In the bhakti guru-shishya relationship the guru is often believed to have supernatural powers, leading to the deification of the guru."
http://en.wikipedia.org/wiki/Guru-shishya_tradition

The Navnath lineage is one should be revered..
"The Navnath (Navanatha or Nao Nath) are the nine saints, Masters or Naths on whom the Navnath Sampradaya, the lineage of the nine gurus is based. They are worshipped collectively as well as individually.[1] This sampradaya or parampara, is a part of the Nath Sampradaya (lineage) of Hindu mythology [2]"
http://en.wikipedia.org/wiki/Navnath

What does a Shishya get from his Guru is a question all the practical humans who always want rather than give , will ask?Materialistic humans have no place here for this give and take.But I must say the experience of the 'Chelas" have been according to their (samarpan) i.e. devotion and dedication.
'Shaktipat"(Anugraha)
http://en.wikipedia.org/wiki/Shaktipat

This is a topic which is unending and not easily fathomable ...And it only is that you need to be as strong a character as 'Valya' to be "Valmiki" ...Valya a 'dacoit' who used to 'way lay' people in the jungles/forests to become a Rishi or Sage and write the 'Ramayana". Alltough one school of thought think otherwise.
" When the fisherman Valya undertook chanting for sixty thousand years he finally became Sage Valmiki. According to another school of thought Sage Valmiki’s real name was Ratnakar, not Valya the fisherman. Valmik is the name of a species of ants which builds anthills. These ants built an anthill on the body of a sage named Ratnakar. Hence people began calling him Sage Valmiki'

http://www.hindujagruti.org/hinduism/knowledge/article/what-is-the-real-meaning-of-ramarajya.html