Plan-Do-Check-Act cycle: A continuous improvement process that is used to identify and solve problems and to improve the effectiveness of a system or process. The PDCA cycle consists of four steps – plan, do, check, and act. In the plan step, a problem is identified, and a solution is developed. In the do step, the solution is implemented and tested. In the check step, the results of the solution are evaluated, and any necessary adjustments are made. In the act step, the solution is refined and implemented on a larger scale. For example, a company may use the PDCA cycle to improve its cybersecurity by identifying potential vulnerabilities, implementing solutions to address those vulnerabilities, and continually monitoring and improving its security systems.