Incense (from Latin incendere "to burn") is composed of aromatic biotic materials, which release fragrant smoke when burned. The term incense refers to the substance itself, rather than to the odour that it produces. It is used in religious ceremonies, ritual purification, aromatherapy, meditation, and for creating a spiritual atmosphere.
Incense is composed of aromatic plant materials, often combined with essential oils. The forms taken by incense differ with the underlying culture, and have changed with advances in technology and increasing diversity in the reasons for burning it. Incense can generally be separated into two main types: "indirect-burning" and "direct-burning". Indirect-burning incense (or "non-combustible incense") is not capable of burning on its own, and requires a separate heat source. Direct-burning incense (or "combustible incense") is lit directly by a flame and then fanned or blown out, leaving a glowing ember that smoulders and releases fragrance. Direct-burning incense is either a paste formed around a bamboo stick, or a paste that is extruded into a stick or cone shape.
Incense was used by Chinese cultures from Neolithic times and became more widespread in the Xia, Shang, and Zhou dynasties. The earliest documented instance of incense utilization comes from the ancient Chinese, who employed incense composed of herbs and plant products (such as cassia, cinnamon, styrax, sandalwood, amongst others) as a component of numerous formalized ceremonial rites.
The oldest source on Indian incense incense are the Vedas, specifically, the Atharva-veda and the Rigveda. Incense-burning was used both to create pleasing aromas and a medicinal tool. Its use in medicine is considered the first phase of Ayurveda, which uses incense as an approach to healing. Incense-making was thus almost exclusively done by monks.
The specific knowledge of incense as a healing tool was assimilated into the religious practices of the time - early Hinduism. As Hinduism matured and Buddhism was founded in India, incense became an integral part of Buddhism as well. Around 200 CE, a group of wandering Buddhist monks introduced incense-making to China.