OPC Classic
OPC Classic is a set of industrial communication standards, originally based on Microsoft's OLE/COM technology, that enables interoperability between automation devices and software applications in industrial control systems. It defines specifications like OPC Data Access (DA), OPC Alarms and Events (A&E), and OPC Historical Data Access (HDA) for real-time data exchange, event handling, and historical data retrieval. Widely used in manufacturing, process control, and SCADA systems, it allows different vendors' hardware and software to communicate seamlessly.
Developers should learn OPC Classic when working on industrial automation, manufacturing execution systems (MES), or supervisory control and data acquisition (SCADA) projects that require integration of legacy equipment or systems relying on Windows-based communication. It is essential for scenarios involving real-time monitoring, data logging, and control of industrial processes where interoperability between diverse devices from multiple vendors is critical, though it is being gradually replaced by OPC UA in modern implementations.