The history of the Arabic alphabet shows that this abjad has changed since it arose. It is thought that the Arabic alphabet is a derivative of the Nabataean variation (or perhaps the Syriac variation) of the Aramaic alphabet, which itself descended from the Phoenician alphabet, which among others gave rise to the Hebrew alphabet and the Greek alphabet. It has been used since the 4th century AD, but the earliest document, an inscription in Arabic, Syriac and Greek, dates from 512 AD. This version of the Arabic alphabet used includes only 22 letters, of which only 15 are different, being used to note 28 phonemes.
It seems that the Nabataean alphabet became the Arabic alphabet thus:
• In the 6th and 5th centuries BC, north-Semitic tribes immigrated and founded a kingdom centered around Petra, in what is now Jordan. These people , spoke probably a form of Arabic.
• In the 2nd century AD, the first known records of the Nabataean alphabet were written, in the Aramaic language (which was the language of communication and trade), but including some Arabic language features: the Nabataeans did not write the language which they spoke. They wrote in a form of the Aramaic alphabet, which continued to evolve; it separated into two forms: one intended for inscriptions (known as "monumental Nabataean") and the other, more cursive and hurriedly written and with joined letters, for writing on papyrus. This cursive form influenced the monumental form more and more and gradually changed into the Arabic alphabet.
The Arabic alphabet contains 28 letters. One interesting feature of Arabic is the multiple forms of a single letter. Depending on where in a word a letter appears, it could appear as an initial form (beginning of word), final form (end of word), or medial form (anywhere else). In addition, if the word has only one letter, than the isolated form is used. Words are written in horizontal lines from right to left, numerals are written from left to right
Due to the influence of Islam, the Arabic alphabet is one of the most widespread writing systems in the world, found in large parts of Africa and Western and Central Asia, as well as in ethnic communities in East Asia, Europe, and the Americas.
Further information and links: