Casbah Udine 

As-Salamu Alaykum (..) is an Arabic language greeting used in both Muslim and Christian cultures. It means "Peace be upon you." It is also transliterated as Assalamu 'Alaikum or As-salaamu Alaikum. The traditional response is wa 'Alaykum As-Salam, meaning "and on you be peace."

This type of greeting is common in the Middle East; it is similar to the Hebrew greeting of shalom aleichem.

The greeting is almost always accompanied by a handshake (when exchanged between persons of the same gender). The exception is Eid, when the hand shake is customarily preceded by three embraces. This practice however is not based on any Islamic ruling.

In Arabia the greeting is associated with three light kisses. In the Indian subcontinent the saying of Salaam is often accompanied with an obeisance, performed by bowing low and placing the right palm on the forehead. Neither of these is derived from Islamic custom, but are based in cultural traditions.

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Islamic rulings related to the use of the greeting

It is also preferred to use the greeting when arriving and also when leaving. It was reported that Abu Hurayrah said “When one of you joins a gathering, let him say salaam. When he wants to get up and leave, let him say salaam. The former is not more important than the latter.” (Saheeh - at-Tirmidhi)

According to hadith the Islamic prophet Muhammad was asked who should "begin" the salam greeting, and he said: "The one who is riding should greet the one who is walking, and the one who is walking should greet the one who is sitting, and the smaller group should greet the larger group." (Saheeh - Al-Bukhaari, 6234; Muslim, 2160)

It is also stated that one should give the Salam greeting upon entering a house, even if the house is empty. This is based upon the verse of the Qur'an: "But when you enter the houses, greet one another with a greeting from Allah (i.e. say: As Salaamu ‘Alaykum — peace be on you), blessed and good." (al-Noor 24:61)

 The trend of shortening the greeting to acronyms such as A.S. or asa is disliked[citation needed], however it is becoming common amongst internet users in chat rooms and by people using SMS. As the full word is not written, it is disliked, however the meaning is usually understood by the recipient. Other variations of this are adding 'wr wb' at the end as well. This trend is similar to writing (S) or 'saws' in place of 'Sallallaahu `Alayhi wa Sallam'.