Dhikr
The Arabic word Dhikr means remembrance. Another word is Dhikrullah (remembrance of God).
Dhikr is a kind of worship to God. It is often performed by the Sufis in congregation, and each Sufi order has its special kind of Dhikr. However all Muslims must do dhikr.There are many benefits of doing Dhikr according to Islamic theology.Such as the fact that it is a polisher of the heart, a way of gaining closeness to Allah, one can even gain trees in Paradise for it.