Iran has a population of around 87 million, making it one of the most populous countries in the Middle East. The population is young and, by regional standards, highly educated — literacy is above 85% and university enrollment is among the highest in the region, with women making up a majority of university students.
Ethnicity is more diverse than the label "Persian" suggests. Ethnic Persians make up roughly 61% of the population. Azeris (Azerbaijani Turks) account for around 16–24% and are concentrated in the northwest — Tabriz is their main city. Kurds (around 10%) live primarily in the west and northwest. Lurs, Baluch, Arabs, Mazandaranis, Gilaks, and Turkmen make up the rest. Iran is genuinely multi-ethnic, and regional identity is strong.
Languages: Farsi (Persian) is the official language and the language of education, government, and culture. It is spoken as a first language by about 58% of the population and understood by virtually everyone. Azeri Turkish is the first language of a large minority in the northwest. Kurdish, Luri, Arabic, Baluchi, and Turkmen are spoken in their respective regions. English is widely studied and many young Iranians in cities speak it reasonably well; older generations are more likely to know French or German.
Religion: Around 99% of Iranians are Muslim. Of these, approximately 90–95% are Shia Muslim, which distinguishes Iran from most of its Sunni-majority neighbors and gives Iranian Islam its particular character: the commemoration of Imam Hussein's martyrdom at Karbala is central to Shia identity and produces intense religious observance around the month of Muharram. The remaining 5–10% are Sunni, concentrated among Kurds, Baluch, and Turkmen. Small communities of Zoroastrians, Jews, Armenian and Assyrian Christians, and Baha'i also exist, though the Baha'i community faces state discrimination.
Ta'arof is the Persian system of polite social conduct, involving elaborate offers and counter-offers. When an Iranian shopkeeper says your money is not good (pul-e shoma qabul nist), they mean they would be honoured to give it to you free — but you are expected to decline and pay. When invited to dinner, a first refusal is expected before accepting. It can be confusing to newcomers but is fundamentally generous in spirit. Iranians are often surprised and delighted when foreign visitors understand the system.