Types of Guru and Gurumantra

Importance of a Guru is exceptional in the life of a disciple, because he cannot realise God without the Guru. What is the difference between Guru, Sadguru and Parātpar Guru? How to recognise a fake Guru? What are the attributes of a true Guru? What are the misconceptions about Gurumantra? Which is the true Gurumantra? etc. Such issues have been dealt with in this Holy text.