A diya, diyo, deya, deeya, dia, divaa, deepa, deepam, deep, deepak or saaki (Sanskrit: दीपम्, romanized: Dīpam) is an oil lamp made from clay or mud with a cotton wick dipped in oil or ghee. These lamps are commonly used in the Indian subcontinent and they hold sacred prominence in Hindu, Sikh, Buddhist, and Jain prayers as well as religious rituals, ceremonies and festivals including Diwali.
Clay diyas are symbolically lit during prayers, rituals, and ceremonies; they are permanent fixtures in homes and temples. The warm, bright glow emitted from a diya is considered auspicious, regarded to represent enlightenment, prosperity, knowledge and wisdom. Diyas represent the triumph of light over dark, good over evil with the most notable example of this being on the day of Diwali. Diwali is celebrated every year to celebrate the triumph of good over evil as told in the Hindu epic, the Ramayana. Diwali marks the day Rama, Sita, and Lakshmana returned home to Ayodhya after 14 years in exile, after the defeat of Ravana. According to tradition, to welcome Rama, Sita, and Lakshmana home, the citizens of Ayodhya are said to have lit up the streets with diyas. They are regarded to be associated with Lakshmi in Hindu iconography and worship.
Traditionally, diyas are lit every morning within Hindu temples.
Lit diyas that are placed before deities during prayer in temples and then used to bless worshippers is referred to as an arati.
A similar lamp called a butter lamp is used in Tibetan Buddhist offerings as well.
Birth: The lighting of diya is also part of the Hindu religion rituals related to birth.
In terms of the choice of material, the kiln fired earthenware lamps followed by the metallic lamps with multiple wicks, mostly of brass known as Samai, are the most common, though other materials are also used such as patravali floating lamp made from leaves or permanent lamps made of stones.
In terms of wick design, diyas with one wick are most common, followed by the two wick style, but other variations such as four, five or seven wick lamps are also made.
In terms of overall lamps design, the ornamental lamps come in various designs. The iconic Nachiarkoil lamp, also known as "Annam lamp", is produced exclusively in by the Pather (Kammalar) community in Nachiyar Koil of Tamil Nadu.