Who is the Brahman?

Who is the Brahman whom we worship and try to attain? It is the Brahman who gives rise to forms, sound, scent, taste and names. There is a Brahman who entered the body through the breath of life. Is he the true Brahman? There is also a Brahman who entered the body through the brahmarandhra. Is he the true Brahman?

The heart, the mind and the organs of sense seem to be different. Man has traits like consciousness, imagination, patience and the power of thought. He experiences feeling like remembrances and unhappiness. He performs acts, desires, objects and knows various arts. But all of these are merely names. All of these are manifestations of the Brahman.

"Upanishad"