Sri Rudram, also known as Rudraprasna, is a hymn devoted to Lord Shiva. It is part of the Krishna Yajur Veda and one of the greatest of the Vedic hymns .
Sri Rudram is in two parts. The first part, is known as Namakam because of the repeated use of the word "Namo" in it. In this sacred hymn the devotee repeatedly salutes the Lord who pervades the animate and the inanimate, tangible and intangible, visible and invisible aspects of creation.
The second part of the Rudram, is known as Chamakam because of the repeated use of the words "Cha me". The devotee prays to the Lord for blessings and benefits both in this world and beyond.
The Rudram mantras are potent and full of power. But it manifests only if we chant it with full of faith.