The most prominent theoretical practice of Hindu Tantra was the Pratyabhijna School of non-dual Kashmir Saivism. This was developed by Utpaladeva in c. 900 – c. 950 CE, and Abhinavagupta in c. 950 – c. 1025 CE. The Pratyabhijna theory construes the emanation and management of the universe by God Siva through his power and companion, Shakti as self-recognition which surpasses human understanding. The ideology believes that existence is formed by the action of God. There are other critical characteristics that are associated with the Pratyabhijna which include theorization of the relationship between religion and philosophical rationality, epistemic diversity, syntax and semantics of indexicals and agency, and philosophical psychology.
Kashimir Shaivism is believed to be above Shaiva Siddhanta, which is a double tradition that scholars deem standardized tantric Shaivism. The goal of Shaiva Siddhanta to become an ideological distinct Shiva, through the grace of Shiva, was substituted with the recognition of oneself as a distinct Shiva who is the total of a universe. This means spiritual practice, also known as sadhana is very critical in order to achieve moksha. There are basically four different techniques highlighted by Kashmir Shaivism to achieve this: anavopaya (technique of body); sambhavopaya (technique of Consciousness); saktopaya (technique of mind); and anupaya (the ‘methodless’ technique).
Taking learnings from the monistic tantric system, the popular Trika Shaivism explores teachings from the shrutis, like the monistic Shiva Sutras of Vasugupta, Bhairava Tantras, and the Bahgavad Gita, which has highlights known as Gitartha Samgraha. This highlight was created by Abhinavagupta. There are also various teachings that are derived from Tantraloka of Abhinavagupta which was outstanding amid the cosmic body of smritis used by Kashmir Shaivism.
Generally, the total documented tradition of the Shaivism can be grouped into three different fundamental aspects, namely, Spanda Satra, Pratyabhijna Sastra, and Agama Sastra.
Spanda Sastra, whose major work, Spanda Karika, is developed by Bhatta Kallata, a strong devotee of Vasugupta. It is essential to mention that the work comes with various commentaries. Out of the commentaries, there are two important ones that stood out; Spanda Sandoha, and Spanda Nirnaya. Spanda Sandoha focuses on the first set of verses of Spanda Karika and Spanda Nirvaya contains the complete text.
Pratyabhijna Sastra refers to the writings that have majorly metaphysical contents. As a result of the extremely strong intellectual and spiritual content level of the writings, this section of the written tradition is rarely accessible by those that are not initiated. However, this body of writing focuses on the most direct and simplest form of spiritual realization.
Agama Sastra refers to the writings believed to have direct revelation from Siva. It is believed that the writings were initially orally communicated from the master to the devoted disciple. These writings include critical works like Sivasutra, Rudrayamala Tantra, Vijnana Bhairava Tantra, Malinivijaya Tantra, Netra Tantra, Svacchanda Tantra, and Mrgendra Tantra, among others.