The official weekend holiday in Iran is Friday although many organizations are open half-day on Thursday. Generally we can divide Persian holidays into religious and national, while both are banking and legal holidays too. There are also holidays for Christian, Jewish, and Zoroastrian minorities, but they are not countrywide ones.
1.Religious Holidays: Iranian religious holidays are based on lunar system while the Persian calendar is based on Solar system, both launched from the exodus of Prophet Muhammad from Mecca to Medina. Hence, within one solar year some religious holidays are observed twice. Religious holidays are subject to change depending upon the official sighting of the moon. The new moon is seen in Arab countries one day earlier, thus there is a difference of one day in important religious days in Iran and the Arab states. Here are the most commonly observed religious holidays:
Eyd-e-Ghorban (happy holiday)
Eyd-e-Ghadir (happy holiday)
Tasooa (mourning holiday)
Ashoora (mourning holiday)
Demise of Prophet & Martyrdom of Emam-Hassan (mourning holiday)
Martyrdom of Emam Reza (mourning holiday)
Birthday of Prophet & Emam Ja'far (happy holiday)
Martyrdom of Hazrat-e-Fatemeh (mourning holiday)
Birthday of Hazrat-e-Ali (happy holiday)
Mission of Prophet (happy holiday)
Birthday of Hazrat-e-Ghaem (happy holiday)
Martyrdom of Hazrat-e-Ali (mourning holiday)
Eyd-e-Fetr (end of Ramadan) (happy holiday)
Martyrdom of Emam Ja'far (mourning holiday)
2.National holidays: Iranian National holidays are based on Persian solar calendar and they are always fixed. The solar year consists of the duration of one full orbit of the Earth around the Sun. Owing to this difference the days in the lunar and solar calendars do not overlap and there are 32 solar years in every 33 lunar years. A solar year consists of 365 days while there are only 354 days in every lunar year. Here are the most commonly observed national holidays:
11 February, Glorious Victory of Islamic Revolution of Iran
20 March, Oil Industry Nationalization
21 March, Iranian New Year (Norooz)
22 March, Iranian New Year
23 March, Iranian New Year
1 April, Iranian National Day
2 April, 13 of Norooz (Nature Day)
4 June, Demise of Emam Khomeini
5 June, 15th Khordad Uprising
A complete Iranian name is composed of two parts; a family name (surname) and a given name. The surname is usually passed down from father to children. Some are named after their birth place, while others are named after natural sights or virtues. The women still kept their surname after marriage. The given name is often composed of one or two characters that some are Arabic and some old Persian.
We usually address an Iranian person by his or her family name. Otherwise it can be considered impolite; unless you are longtime, good friends. Following the surname, use "Aghaye" (Mr.) for men, and "Khanume" (Mrs. , Ms.) for women. Using the same western custom, we suggest that you please add professional title after his or her family names when addressing a very important person.
Time in Tehran is three and a half hours ahead of GMT. After you have set your watch to the local time ,you should bear in mind that when you are having your breakfast in Tehran, people in western Europe are sound asleep. Consider this when making long distance phone calls. Depending from where you have come, it may be too late or too early for making a phone call or expecting one.
Weights and Measures:
Like most of the countries of the world ,Iran uses the well known metric system in which length is measured by meters and weight by kilograms. To convert metric system quantities into British or American measures you may use the conversion tables which usually appear at the end of dictionaries, calendars, etc.
As far as electrical power supply is concerned, the owner supply in Iran is 220 V but in some hotels conversion to 110 V may also be available.