Baba Baidyanath Dham: Why is Baba Baidyanath Dham of इतिहास.देवघर associated with devotion to Ravana called 'Kamna Linga'?

With the beginning of the holy month of Sawan, the eyes of Shiva devotees turn to Deoghar, located in the Santhal Pargana of Jharkhand. But did you know that this shrine is among the 12 Jyotirlingas?