There are two Śaiva Siddhāṅta schools: pluralistic theism, in the lines of Aghoraśiva and Meykandar, and Tirumular’s monistic theism. While differing slightly, they share a religious heritage of belief, culture and practice. In South India, their points of agreement are summarized as guru, preceptor; Linga, holy image of Śiva; saṅga, fellowship of devotees; and valipadu, ritual worship.