Shiv Vidyeshwara Samhita
The Shiva Purana contains chapters with Shiva-centered cosmology, mythology, relationship between Gods, ethics, yoga, tirtha (pilgrimage) sites, bhakti, rivers and geography, and other topics. The text is an important source of historic information on different types and theology behind Shaivism in early 2nd-millennium CE. The oldest surviving chapters of the Shiva Purana have significant Advaita Vedanta philosophy, which is mixed in with theistic elements of bhakti.
In the 19th and 20th century, the Vayu Purana was sometimes titled as Shiva Purana, and sometimes proposed as a part of the complete Shiva Purana. With the discovery of more manuscripts, modern scholarship considers the two texts as different, with Vayu Purana as the more older text composed sometime before the 2nd-century CE. Some scholars list it as a Mahapurana, while some state it is an Upapurana.