Persian is normally written without short vowel marks — readers infer vowels from context. Diacritics (harakat / اعراب) are small marks placed above or below letters to indicate exact pronunciation. They appear in the Qur'an, children's books, dictionaries, and wherever precise reading is required. Knowing them helps you decode any fully-voweled Persian or Arabic text.

Persian uses Eastern Arabic numerals (۰–۹), distinct from Western Arabic (0–9). They are written left-to-right like Western numbers. Dates, prices, and page numbers in Persian text all use these forms. The shapes differ slightly from Arabic numerals — compare ۴ (four) and ۶ (six) especially.

Direction: Persian is written right-to-left. Only numbers and foreign words embedded in Persian text run left-to-right.
Cursive: Letters connect to their neighbours in almost all cases. Non-connecting letters (ا، د، ذ، ر، ز، ژ، و) only connect to the letter on their right.
No capital letters: Persian has no upper/lower case distinction.
Hamza (ء): A glottal stop mark, can appear on its own or on a carrier letter (أ، إ، ؤ، ئ). In modern Persian its use is simplified compared to Arabic.
Alef variants: آ (alef with madda, /â/) is a very common initial vowel. اَ (alef with fatha) and اِ (alef with kasra) appear in fully voweled text.