Hinduism is an ancient religion. It is the only surviving 'pagan' faith. There may be various reasons behind it.
The most important aspect of Hinduism is 'Unity in Diversity.
Hindus may worship different deities, but ultimately all fuse into the all-pervading 'Brahman'; the ultimate reality. It is something that cannot be described in words. It is as abstract as it can get. Everything in this universe is a part of this 'supreme reality'. However, there is something more to it.
Who is 'Bhairav'?
Amidst the 'Trimurti' of 'Brahma-Vishnu-Mahesh', Shiva (Mahesh) is the supreme power known for his 'destructive' nature. This destructive form of Shiva is called 'Bhairav'.
'Kaal Bhairav' is a terrifying form of Shiva. He is a destructive wanderer who destroys everything that comes his way. It is said that there are 64 Bhairavs in total and their 'supreme commander' is known as 'Kaal Bhairav'.
What does 'Bhairav' mean?
In simple words 'Bhairav' means 'terrifying'. However, the interpretation can get a bit nuanced. Some say that 'Bhairav' is the deity who acts as a guardian for his 'Bhakts' and protects them from negative energies. On the other hand, it is said that 'Bha' stands for 'creation', 'Ra' stands for 'conservation' and 'Va' stands for 'annihilation'. Therefore, the name 'Bhairava' is a combination of all the supreme forces which shape the universe.
The Eight Incarnations of 'Bhairav'
Kapal Bhairav: Destroys non-productive attitude.
Krodh Bhairav: Gives strength for important decisions.
Ruru Bhairav: Destroys adversaries.
Samhaara Bhairav: Destroys bad 'karma'.
Chand Bhairav: Helps in boosting confidence.
Bheeshan Bhairav: Eliminates negative and dark forces.
Asitang Bhairav: Makes people creative.
Unmattha Bhairav: Helps in speaking skills.
On 'Kaal Bhairav Jayanti' it is believed that the true devotees of 'Bhairav', who worship him with utmost devotion get the strength to fight all the negative aspects of life. (KB)