The Arabic alphabet has 28 letters. Adaptations of the Arabic script for other languages, such as Persian, Ottoman, Sindhi, Urdu, Malay or Pashto, Arabi Malayalam, have additional letters, shown below. There are no distinct upper and lower case letter forms.
Many letters look similar but are distinguished from one another by dots (’i‘jām) above or below their central part, called rasm. These dots are an integral part of a letter, since they distinguish between letters that represent different sounds. For example, the Arabic letters transliterated as b and t have the same basic shape, but b has one dot below, ب, and t has two dots above, ت.
Both printed and written Arabic are cursive, with most of the letters within a word directly connected to the adjacent letters.