Yamalas
The Yamalas constitute a class of tantric literature. They indicate a great development in the tantric sadhana. The principal Yamalas are eight in number and are said to be communicated by the eight Bhairavas. They are: Rudra, Kanda or Skanda, Brahma, Vishnu, Yama, Vayu, Kubera, and Indra. Whereas the Shiva tantras represent the Rudra or Sadashiva tradition, the Yamalas represent the Bhairava tradition.
These Bhairavas seem to have been human teachers who had attained complete spiritual emancipation and had almost become Shiva. The Yamalas try to define the various tantric traditions by introducing a great variety of tantric pantheon. To be more precise, the Brahma Yamala speaks of three currents in the tantric tradition: dakshina, the southern; vama, the left; and madhyama, the central. These represent three powers of Shiva and are characterised by the predominance of sattva, rajas, and tamas respectively.
The Yamalas affiliate a large number of local cults, and open up the field of tantric sadhana to people of other castes. Thus they at once preserve the orthodox tradition of tantras of earlier period and assume a heterodox nature themselves.
The supplementary literature of the Yamala group indicates a new orientation of the tantric culture. The sadhanas of the agamas assume in them a more pronounced character of Shaktism.
The tradition of the agamas developed through two channels — the exoteric and the esoteric. The former was continued as pure Shaivism with a view to attaining salvation. The latter was continued as Shaktism with greater emphasis on the various Shakti cults, not so much to attain salvation as to gain control over the forces of nature.