who is guru ?

1. Guru !
गुर

2. G u R u
G u R u
or
Ji you are you

3. Anubhavam anu guru =
Experience is the teacher
Malayalam version ….

4. Source : http://en.wikipedia.org/wiki/Guru
The word guru, a noun, means "teacher" in Sanskrit
satguru (literally: true teacher),
The Vishnu Smriti and Manu Smriti regard the Acharya (teacher/guru)