What is "diwan-e-ghalib"

Diwan-e-Ghalib is a famous poetry book written by a famous Persian and Urdu poet Mirza Asadullah Khan Ghalib. It is a collection of the Ghazals of Ghalib. Though it does not include all his Ghazals as he was too choosy to include all of his Ghazals, still in many other copies of diwan e Ghalib the Urdu scholars have tried to collect all his precious works. It is the only book written by Ghalib. A lot of authentic copies of diwan e ghalib exist like Nuskha e Nizami, Nuskha e Arshi, Nuskha e Hamidiya (Bhopal), Nuskha az Ghulam rasool Mehr.