As-salamu alaykum

As-salamu alaykum (Arabic: ٱلسَّلَامُ عَلَيْكُمْ, romanized: as-salāmu ʿalaykum, pronounced [as.sa.laː.mu ʕa.laj.kum] ), also written salamun alaykum and typically rendered in English as salam alaykum, is a greeting in Arabic that means 'Peace be upon you'. The salām (سَلَام, meaning 'peace') has become a religious salutation for Muslims worldwide when greeting each other, though its use as a greeting predates Islam, and is also common among Arabic speakers of other religions (such as Arab Christians and Mizrahi Jews).
In colloquial speech, often only salām, 'peace', is used to greet a person. This shorter greeting, salām (سَلَام), has come to be used as the general salutation in other languages as well.
The typical response to the greeting is wa-ʿalaykumu s-salām (وَعَلَيْكُمُ ٱلسَّلَامُ [wa.ʕa.laj.ku.mu‿s.sa.laːm] , 'and peace be upon you'). In the Quranic period one repeated as-salamu alaykum, but the inverted response is attested in Arabic not long after its appearance in Hebrew. The phrase may also be expanded to as-salāmu ʿalaykum wa-raḥmatu -llāhi wa-barakātuhᵘ̄ (ٱلسَّلَامُ عَلَيْكُمْ وَرَحْمَةُ ٱللَّٰهِ وَبَرَكَاتُهُ [as.sa.laː.mu ʕa.laj.kum wa.raħ.ma.tu‿ɫ.ɫaː.hi wa.ba.ra.kaː.tu.hu], 'Peace be upon you, as well as the mercy of God and His blessings').
The use of salām as an Arabic greeting dates at least to Laqit bin Yamar al-Ayadi (6th century), and cognates in older Semitic languages—Aramaic šlāmā ʿalḵōn (ܫܠܵܡܵܐ ܥܲܠܟ݂ܘܿܢ) and Hebrew shalom aleichem (שָׁלוֹם עֲלֵיכֶם shālôm ʻalêḵem)—can be traced back to the Old Testament period.
The phrase is normally pronounced according to local dialects of speakers and is very often shortened. For example, in Egypt, the phrase and its response are pronounced [sæˈlæːmu ʕæˈleːku] and [we ʕæˈleːkom es.sæˈlæːm].
The expression commonly 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 follows (note: according to the standard pronunciation rules of Classical Arabic, the last short vowel in each word is not pronounced in pausa):
A third-person variant, ʿalayhi as-salām, "peace be upon him", is often used by Muslims for prophets other than Muhammad and other holy personalities, such as angels.
According to Islamic tradition, the origin of the greeting "Peace be upon you" dates back to the first human, Adam:
Abu Huraira reported: The Prophet, peace and blessings be upon him, said, "Allah said: Go and greet with peace these groups of assembled angels and listen to how they greet you, for this will be the greeting among your progeny. Adam said: Peace be upon you. The angels said: Peace be upon you and the mercy of Allah. Thus, they added the mercy of Allah"
The final Prophet said, "None of you will enter paradise until you believe and you will not believe until you love one another. Shall I not tell you about something which, if you do it, you will love one another? Spread salaam amongst yourselves."
It is also stated that one should give the Salam greeting upon entering a house. This is based upon a verse of the Quran: "However, when you enter houses, greet one another with a greeting ˹of peace˺ from Allah, blessed and good. This is how Allah makes His revelations clear to you, so perhaps you will understand." (An-Nur 24:61).
The phrase appears a total of 7 times in the Quran, each time as salamun ʿalaykum (Arabic: سَلَامٌ عَلَيْكُمْ). In Classical Arabic, used in the Qur'an and early Hadith manuscripts, the phrase is spelled as "ٱلسَّلَٰمُ عَلَيْكُمْ وَرَحْمَتُ ٱللَّٰهِ وَبَرَكَٰتُهُ". In Rasm, it is written as "السلم علىکم ورحمٮ ال‍له وٮرکٮه".
Other variants, such as salamun ʿalā (سَلَامٌ عَلَىٰ), or the term salam (سَلَام) alone is also mentioned in several other Ayahs of the Qur'an.