what is SCADA and how to integrate with SAP

Hi all,

I am new to SCADA and i would like to know

1. what is SCADA

2. Purpose of SCADA

3. how to integrate SCADA with SAP

4. In SAP for which module we can use SCADA

5. Wether SCADA is used for only PM(Plant Maintanence) in SAP

Thnx in advance,