# programmable logic controller > digital computer used for automation of electromechanical processes **Wikidata**: [Q188674](https://www.wikidata.org/wiki/Q188674) **Wikipedia**: [English](https://en.wikipedia.org/wiki/Programmable_logic_controller) **Source**: https://4ort.xyz/entity/programmable-logic-controller ## Summary A programmable logic controller (PLC) is a digital computer used for the automation of electromechanical processes. It is classified as a type of industrial PC and controller, designed to interface with peripheral devices to manage industrial operations. Commonly referred to by the abbreviation PLC, it serves as a robust computing solution for automation environments. ## Key Facts * **Definition:** A digital computer used specifically for the automation of electromechanical processes. * **Classification:** It is a subclass of both **industrial PC** and **controller** (a computing device that interfaces with peripheral devices). * **Related Trademark:** Associated with **SIMATIC**, a trademark in the field inceptioned in **1958**. * **Community Size:** The Reddit community `r/PLC` has **58,624** followers (as of May 23, 2023). * **Product Taxonomy:** Classified under Google Product Taxonomy ID **7263** ("Business & Industrial > Automation Control Components > Programmable Logic Controllers"). * **Trade Code:** Holds the MCN Code **8537.10.20**. * **Aliases:** Also known as a programmable controller, SPS, automate programmable, and controlador logico programable. ## FAQs ### Q: What exactly is a programmable logic controller? A: A programmable logic controller (PLC) is a digital computer used for the automation of electromechanical processes. It functions as a specialized controller to manage machinery or processes in industrial settings. ### Q: Is a PLC considered a computer? A: Yes, a PLC is explicitly defined as a digital computer and is classified as a subclass of an industrial PC. Unlike standard personal computers, it is built to withstand harsh industrial environments and specific automation tasks. ### Q: What is the historical context of PLC technology? A: While the device itself is a modern computing tool, it is closely related to the **SIMATIC** trademark, which was established in **1958**, marking the early era of industrial automation technology. ## Why It Matters The programmable logic controller is a critical component in the landscape of modern industrial automation. By functioning as a specialized digital computer, it bridges the gap between high-level computing logic and the physical reality of electromechanical processes. Its classification as an "industrial PC" highlights its role in bringing computational power to the factory floor, allowing for precise control over machinery that standard computers cannot handle directly. The existence of a specific Google Product Taxonomy (ID 7263) for these devices underscores their distinct role within the "Business & Industrial" sector, specifically under "Automation Control Components." This distinction matters because it represents the move from manual control to automated, logic-based management of complex systems. With a dedicated user base of over 58,000 followers on social platforms like Reddit, the PLC remains a vibrant and evolving technology essential for engineers and technicians managing modern production and automated systems. ## Notable For * **Specialized Computing:** Distinguished from general-purpose computers by its specific design as an **industrial PC** for hardening against industrial environments. * **Automation Core:** Acts as the primary **controller** for the automation of electromechanical processes, interfacing directly with peripheral devices. * **Global Standardization:** Recognized globally under various aliases (PLC, SPS, automate programmable) and tracked via specific trade codes (MCN 8537.10.20). * **Historical Ties:** Connected to the **SIMATIC** brand, which dates back to **1958**, indicating long-standing development in this field. ## Body ### Definition and Classification The programmable logic controller (PLC) is defined fundamentally as a **digital computer** utilized for the **automation of electromechanical processes**. In the hierarchy of computing devices, it is recognized as a **subclass of industrial PC** and a **controller**. As a controller, it serves as a computing device that interfaces with more peripheral devices to manage inputs and outputs. It is distinct from other controller types, such as video game controllers, by its application in industrial and business environments rather than entertainment. ### Nomenclature and Aliases The entity is recognized globally under several names and codes: * **Common Aliases:** PLC, programmable controller, SPS, automate programmable, controlador logico programable, and 可编程逻辑控制器. * **Identifiers:** * **Wikidata ID:** Q201656 * **MCN Code:** 8537.10.20 * **Google Product Taxonomy:** 7263 (Business & Industrial > Automation Control Components > Programmable Logic Controllers) * **YSO ID:** 15147 ### Historical and Commercial Context The knowledge base notes a significant relationship to **SIMATIC**, identified as a trademark in this domain. The inception of the SIMATIC brand is recorded as **1958**. Commercially, the PLC is categorized strictly under business and industrial automation. It is a distinct category in major knowledge bases, including the National Library of Spain (ID: XX531788) and KBpedia (ID: ProgrammableLogicController). ### Community and Digital Presence The PLC maintains a significant digital footprint, particularly in technical communities. * **Social Media:** The primary Reddit community (`r/PLC`) was created on May 6, 2009. As of May 23, 2023, it has **58,624** followers with the title "PLC - Programmable Logic Controllers." * **Wikipedia:** The topic has a sitelink count of **49** across various languages, including Arabic, German, English, and Greek, indicating broad global relevance. ## References 1. Freebase Data Dumps. 2013 2. [Source](http://datos.bne.es/tema/XX531788.html) 3. [PLC - Programmable Logic Controllers](https://www.reddit.com/r/PLC/) 4. KBpedia 5. [OpenAlex](https://docs.openalex.org/download-snapshot/snapshot-data-format)