Where we applied plc scada?

We apply both in Automation. Automation is the process of controlling equipments, industrial machine or a whole system. Plc is the programmable Logic Controllers and scada  is Supervisory Control and Data Acquisition. Both are used for controlling.

Both are apply a real time industry process control.

Both PLC and SCADA are mainly used in process control industry.

There are used for Supervision, Monitoring and controlling of different processes.