Knowledge was a term used by Shri Hans Ji Maharaj (Hans Rawat) to denote a formulation of four specific meditation

Meditation

Meditation is any form of a family of practices in which practitioners train their minds or self-induce a mode of consciousness to realize some benefit....

 techniques that were imparted in a process of initiation. The term has continued to be used by two of Shri Hans Ji Maharaj’s sons, Satpal Maharaj

Satpal Maharaj

Satpal Maharaj is a member of the lower house of the Parliament of India for the Indian National Congress party....

 (Satyapal Rawat) and Prem Rawat

Prem Rawat

Prem Pal Singh Rawat , also known as Maharaji and formerly known as Guru Maharaj Ji and Balyogeshwar, teaches a meditation practice he calls Knowledge....

 (Maharaji, Guru Maharaj Ji).
According to David Barret, these techniques have some similarities to techniques in Sant Mat

Sant Mat

Sant Mat was a loosely associated group of teachers that became prominent in the northern part of the Indian sub-continent from about the 13th century...

 derived movements and may be derived from Surat Shabd Yoga

Surat Shabd Yoga

Surat Shabd Yoga or Surat Shabda Yoga is a form of spiritual practice that is followed in the Sant Mat and many other related spiritual traditions...

.