This document discusses programmable logic controllers (PLCs) and supervisory control and data acquisition (SCADA) systems used in industrial automation. It defines automation and describes how PLCs and SCADA systems are commonly used to automate industrial processes. The document outlines the basic components and programming of PLCs, provides examples of PLC brands and types, and describes some common applications of PLCs and SCADA systems in industries like manufacturing, food and beverage, and water treatment.