These are represented as the five faces of Shiva and are associated in various texts with the five elements, the five senses, the five organs of perception, and the five organs of action. Doctrinal differences and, possibly, errors in transmission, have resulted in some differences between texts in details of how these five forms are linked with various attributes. The overall meaning of these associations is summarized by Stella Kramrisch:Through these transcendent categories, Śiva, the ultimate reality, becomes the efficient and material cause of all that exists.According to the "Pañcabrahma Upanishad":One should know all things of the phenomenal world as of a fivefold character, for the reason that the eternal verity of "Śiva" is of the character of the fivefold Brahman. ("Pañcabrahma Upanishad" 31)
Puranic scriptures contain occasional references to "ansh" – literally 'portion, or avatars of Shiva', but the idea of Shiva avatars is not universally accepted in Saivism. The Linga Purana mentions twenty-eight forms of Shiva which are sometimes seen as avatars, however such mention is unusual and the avatars of Shiva is relatively rare in Shaivism compared to the well emphasized concept of Vishnu avatars in Vaishnavism. Some Vaishnava literature reverentially link Shiva to characters in its mythologies. For example, in the "Hanuman Chalisa", Hanuman is identified as the eleventh avatar of Shiva. The "Bhagavata Purana" and the "Vishnu Purana" claim sage Durvasa to be a portion of Shiva. Some medieval era writers have called the Advaita Vedanta philosopher Adi Shankara an incarnation of Shiva.
Main article: Maha Shivaratri
Maha Sivaratri festival is observed in the night, usually in lighted temples or special "prabha" (above).
There is a "Shivaratri" in every lunar month on its 13th night/14th day, but once a year in late winter (February/March) and before the arrival of spring, marks "Maha Shivaratri" which means "the Great Night of Shiva".
Maha Shivaratri is a major Hindu festival, but one that is solemn and theologically marks a remembrance of "overcoming darkness and ignorance" in life and the world, and meditation about the polarities of existence, of Shiva and a devotion to humankind. It is observed by reciting Shiva-related poems, chanting prayers, remembering Shiva, fasting, doing Yoga and meditating on ethics and virtues such as self-restraint, honesty, noninjury to others, forgiveness, introspection, self-repentance and the discovery of Shiva. The ardent devotees keep awake all night. Others visit one of the Shiva temples or go on pilgrimage to Jyotirlingam shrines. Those who visit temples, offer milk, fruits, flowers, fresh leaves and sweets to the lingam. Some communities organize special dance events, to mark Shiva as the lord of dance, with individual and group performances. According to Jones and Ryan, Maha Sivaratri is an ancient Hindu festival which probably originated around the 5th-century.
Another major festival involving Shiva worship is Kartik Purnima, commemorating Shiva's victory on the demons Tripurasura. Across India, various Shiva temples are illuminated throughout the night. Shiva icons are carried in procession in some places.
Thiruvathira is a festival observed in Kerala dedicated to Shiva. It is believed that on this day, Parvathi met Lord Shiva after her long penance and Lord Shiva took her as his wife. On this day Hindu women performs the Thiruvathirakali accompanied by Thiruvathira paattu (folk songs about Parvati and her longing and penance for Lord Shiva's affection).
Regional festivals dedicated to Shiva include the Chittirai festival in Madurai around April/May, one of the largest festivals in South India, celebrating the wedding of Minakshi (Parvati) and Shiva. The festival is one where both the Vaishnava and Shaiva communities join the celebrations, because Vishnu gives away his sister Minakshi in marriage to Shiva.
Some Shaktism-related festivals revere Shiva along with the goddess considered primary and Supreme. These include festivals dedicated to Annapurna such as "Annakuta" and those related to Durga. In Himalayan regions such as Nepal, as well as in northern, central and western India, the festival of Teej is celebrated by girls and women in the monsoon season, in honor of goddess Parvati, with group singing, dancing and by offering prayers in Parvati-Shiva temples.
The ascetic, Vedic and Tantric sub-traditions related to Shiva, such as those that became ascetic warriors during the Islamic rule period of India, celebrate the Kumbha Mela festival. This festival cycles every 12 years, in four pilgrimage sites within India, with the event moving to the next site after a gap of three years. The biggest is in Prayaga (renamed Allahabad during the Mughal rule era), where millions of Hindus of different traditions gather at the confluence of rivers Ganges and Yamuna. In the Hindu tradition, the Shiva-linked ascetic warriors ("Nagas") get the honor of starting the event by entering the "Sangam" first for bathing and prayers.
Shiva has been adopted and merged with Buddhist deities. Left: Daikokuten is a Shiva-Ōkuninushi fusion deity in Japan; Right: Acala is a fierce Shiva adaptation.
The statue of Shiva engaging in the Nataraja dance at the campus of European Organization for Nuclear Research (CERN) in Geneva, Switzerland.
In Shaivism of Indonesia, the popular name for Shiva has been "Batara Guru", which is derived from Sanskrit "Bhattaraka" which means "noble lord". He is conceptualized as a kind spiritual teacher, the first of all Gurus in Indonesian Hindu texts, mirroring the Dakshinamurti aspect of Shiva in the Indian subcontinent. However, the Batara Guru has more aspects than the Indian Shiva, as the Indonesian Hindus blended their spirits and heroes with him. Batara Guru's wife in southeast Asia is the same Hindu deity Durga, who has been popular since ancient times, and she too has a complex character with benevolent and fierce manifestations, each visualized with different names such as Uma, Sri, Kali and others. Shiva has been called Sadasiva, Paramasiva, Mahadeva in benevolent forms, and Kala, Bhairava, Mahakala in his fierce forms. The Indonesian Hindu texts present the same philosophical diversity of Shaivism traditions found on the subcontinent. However, among the texts that have survived into the contemporary era, the more common are of those of Shaiva Siddhanta (locally also called Siwa Siddhanta, Sridanta).
In the pre-Islamic period on the island of Java, Shaivism and Buddhism were considered very close and allied religions, though not identical religions. The medieval era Indonesian literature equates Buddha with Siwa (Shiva) and Janardana (Vishnu). This tradition continues in predominantly Hindu Bali Indonesia in the modern era, where Buddha is considered the younger brother of Shiva.
The worship of Shiva became popular in Central Asia through the Hephthalite Empire, and Kushan Empire. Shaivism was also popular in Sogdia and the Kingdom of Yutian as found from the wall painting from Penjikent on the river Zervashan. In this depiction, Shiva is portrayed with a sacred halo and a sacred thread ("Yajnopavita"). He is clad in tiger skin while his attendants are wearing Sogdian dress. A panel from Dandan Oilik shows Shiva in His Trimurti form with Shakti kneeling on her right thigh. Another site in the Taklamakan Desert depicts him with four legs, seated cross-legged on a cushioned seat supported by two bulls. It is also noted that Zoroastrian wind god Vayu-Vata took on the iconographic appearance of Shiva.