As-salāmu ʿalaykum (Arabic: السَّلَامُ عَلَيْكُمْ [asːaˈlaːmu ʕaˈlajkum]) is a greeting in Arabic that means "peace be upon you". The greeting is a standard salutation among Muslims and is routinely used whenever and wherever Muslims gather and interact, whether socially or within worship and other contexts. The typical response to the greeting is waʿalaykumu s-salām (وَعَلَيْكُم السَّلَام [waʕaˈlajkumu sːaˈlaːm]; "and upon you, peace").
This greeting appears in greatly abbreviated forms in many languages from Malagasy to Urdu as some variant of salām (سَلَام; cf. Persian سلام [sæˈlɒːm]).
The term uses the second person plural masculine, even when used to address one person. It may be modified by choosing the appropriate enclitic pronoun to address a person in the masculine and feminine singular form, the dual form, or the feminine plural form. The conjugations are as follow (note: according to the standard pronunciation rules of Classical Arabic, the last short vowel in each word is not pronounced unless it is followed by another word):
A third-person variant, ʿalayhi as-salām "peace be upon him", is used in reference to prophets.
It is also preferred to use the greeting when arriving and also while leaving. It was reported that Abu Hurairah said “When one of you joins a gathering, let him say 'Peace'. When he wants to get up and leave, let him say 'Peace'. The former is not more important than the latter.” (Hasan hadith reported in Jāmiʿ at-Tirmidhi)