Jawi (جاوي; Acehnese: Jawoë; Malay: Jawi; Malay pronunciation: [d͡ʒä.wi]) is a writing system used for writing several languages of Southeast Asia, such as Acehnese, Banjarese, Betawi, Iranun, Kutainese, Maguindanao, Malay, Mëranaw, Minangkabau, Tausūg, Ternate, and many other languages in Southeast Asia. Jawi is based on the Arabic script, consisting of all 31 original Arabic letters, six letters constructed to fit phonemes native to Malay, and one additional phoneme used in foreign loanwords, but not found in Classical Arabic, which are ca (⟨چ⟩ /t͡ʃ/), nga (⟨ڠ⟩ /ŋ/), pa (⟨ڤ⟩ /p/), ga (⟨ݢ⟩ /ɡ/), va (⟨ۏ⟩ /v/), and nya (⟨ڽ⟩ /ɲ/).
Jawi was developed during the advent of Islam in Maritime Southeast Asia, supplanting the earlier Brahmic scripts used during Hindu-Buddhist era. The oldest evidence of Jawi writing can be found on the 14th century Terengganu Inscription Stone, a text in Classical Malay that contains a mixture of Malay, Sanskrit and Arabic vocabularies. However, the script may have used as early as the 9th century, when Peureulak Sultanate has been established by the son of a Persian preacher. There are two competing theories on the origins of the Jawi alphabet. Popular theory suggests that the system was developed and derived directly from the Arabic script, while scholars like R. O. Windstedt suggest it was developed with the influence of the Perso-Arabic alphabet.