Arabic script is used to write Arabic, Persian, Urdu, Pashto, Ottoman Turkish, Hausa, Punjabi, Malay, Kurdish, and a wide range of other languages worldwide, by over 600 million people. Observant Muslims can generally read the Arabic script as well. It is one of the most widely used scripts in the world. The Arabic script derives from the ancient Nabatean script, with the Syriac script influencing its development. Both were descendants of the older Aramaic script. Letters of the same word are written flowing into one another in cursive fashion, and can have up to four distinct forms based on word position: isolated, initial, medial and final. Isolated letters do not combine with others.

Diacritics are used to represent short vowels, consonant variation and more. Since the script is used to write a wide range of languages, it includes numerous diacritics, additional letters and even modified letter forms across its linguistic range. Many of these are particular to specific linguistic traditions, and are obscure elsewhere. A range of different writing styles are used, often with variations in cursive flow as well. For example, while text in Naskh has a linear cursive flow, text in Nastaliq gradually descends to the baseline from above.