https://tug.org/xetex[XeTeX^] is a typesetting engine derived from Donald Knuth's original https://tug.org/whatis.html[TeX^] software.
However, unlike Knuth's original program, XeTeX natively reads (inputs) UTF-8 encoded Unicode text and, with assistance from its built-in HarfBuzz shaping engine, supports modern font formats such as OpenType (OTF) and SIL's Graphite font technology.