OPL stands for One Point Lesson, which is an operational tool used to educate operators through simple diagrams and words. There are three main types of OPL: basic information sheets about components and maintenance, problem case studies of past issues, and improvement sheets with ways to enhance productivity and quality. OPL is effective for achieving work standards across shifts, communicating important messages clearly, sharing knowledge, and preventing defects through preventative maintenance. When creating an OPL, it should focus on one main point using photos, text, and arrows so the information can be understood quickly within 10 minutes. OPL benefits organizations by improving performance, cost efficiency, product quality, and work culture.