Wikipedia
Kala Bhairava Ashtakam is a Sanskrit Ashtakam, written by Adi Sankara. The hymn illustrates the personality of Kala Bhairava of Kashi (also known as Bhairava), the God of Death. It consists of eight stanzas, characteristic of an Ashtakam.
Kala Bhairava is described as black, naked body entwined with snakes, fangs, garland of skulls, three eyes, weapons for punishment in four hands, with shining golden bells attached to his waist-belt. His dreadful laughter that shatters the entire creation - that has sprung out from the womb of the Creator, control over ghosts and goblins, The Thandava dance that is associated with the annihilation of the world, liberation of Souls from bodies- all pointing out to the fact that he is the God of Death.
Those who study these 8 verses on Kala Bhairava, which are enticing and which are a source of knowledge and liberation, which increase the righteousness of a person and destroy greed, attachment, depression, anger and heat and enable us to move towards the proximity of feet of Shiva (Kala Bhairava) positively.