Short answers, pulled from the story.
Pali is a Middle Indo-Aryan language that serves as the sacred language of Theravada Buddhism and the language of the Tipitaka, the great scriptural collection of that tradition. It is studied mainly to access Buddhist scriptures and is chanted in ritual contexts across Sri Lanka, Myanmar, Thailand, Laos, and Cambodia. On the 3rd of October 2024, the Government of India designated it a classical language of India.
Modern scholars generally regard Pali as originating from a western dialect of Middle Indo-Aryan rather than an eastern one, associating it with the region of western India and pointing to shared features with the Junagadh rock inscription of Rudradaman in Kathiawar. A. K. Warder specifically connects it with the realm of Avanti. It is understood as a hybrid showing features of several Prakrit dialects used around the 3rd century BCE.
The oldest surviving Pali manuscript was discovered in Nepal and dates to the 9th century. It consists of four palm-leaf folios written in a transitional script derived from the Gupta script, preserving a fragment of the Cullavagga. Complete manuscripts of the four Nikayas only exist in examples from the 17th century and later.
The Pali Text Society was founded in 1881 and is based in the United Kingdom. It publishes romanized Pali editions of texts and English translations, and it has been a major force in promoting the study of Pali by Western scholars. It was founded partly to compensate for the very low level of funds allocated to Indology in late 19th-century Britain.
Scholars do not believe Pali is identical to the language the Buddha himself spoke. Bhikkhu Bodhi summarizes current scholarship by stating the language is closely related to the language, or more likely the various regional dialects, that the Buddha himself spoke. Scholars consider it likely the Buddha taught in several closely related dialects of Middle Indo-Aryan that had a high degree of mutual intelligibility.
Pali is chanted in ritual contexts throughout Theravada Buddhist cultures. In Sri Lanka, recitation of the vows of Angulimala is believed to ease the pain of childbirth. In Thailand, chanting a portion of the Abhidhammapitaka is held to benefit the recently departed, a ceremony that can occupy as many as seven working days. The great centers of Pali learning remain in Sri Lanka, Myanmar, Thailand, Laos, and Cambodia.