Instruction List
Instruction List (IL) is a low-level, text-based programming language used primarily in industrial automation and programmable logic controllers (PLCs). It resembles assembly language with mnemonic instructions that directly manipulate memory addresses, registers, and I/O points. IL is standardized under IEC 61131-3 as one of the five PLC programming languages, focusing on simple, sequential execution for control logic.
Developers should learn Instruction List when working with legacy PLC systems, embedded control applications, or scenarios requiring direct hardware manipulation and high performance in industrial automation. It is particularly useful for implementing time-critical functions, debugging low-level code, or maintaining existing systems where IL is the primary language, such as in manufacturing, robotics, or process control industries.