What are the 5 Types of PLC Programming Languages Programmable Logic Controllers (PLCs) are commonly used in industrial automation to control and monitor machinery and processes. There are several programming languages used for PLC programming, each with its own strengths and purposes. Here's an overview of five common types of PLC programming languages: 01 Instruction List 02 Structured Text 03 Sequential Function Charts 04 Function Block Diagram 05 Ladder Logic