Assalamu alaikum is an expression Muslims say whenever they meet one another. It is a statement of greeting meaning "Peace be upon you."
The other forms are: "Assalamu 'Alalikum Wa Rahmatullah," which means:"May the peace and the Mercy of Allah be upon you," and "Assalamu Alalikum Wa Rahmatullahi Wa Barakatuh," which means :"May the peace, the mercy, and the blessings of Allah be upon you."
Other Spellings: Assalamo Alaikum, Asalamo Alaikum
The Hebrew version is Shalom Aleichem
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