Du’ã is asking Allah for help or for the fulfilment of a particular need. It expresses a slave’s helplessness and dependence on Allah, the All-Powerful and Merciful. It is the channel through which one gets directly in touch with one’s Creator.
The purpose of man’s creation is worship and according to a Hadeeth, ‘Du’ã is the essence of worship’. (Tirmizi) And according to another Hadeeth, ‘Du’ã is the worship’. (Tirmizi)