SOP is the abbreviation of English Standard operation Procedure, which means standard operating procedure in Chinese. It is a document describing the operation process, which is used to specify the specific steps and methods of a certain work to ensure that the work can be carried out in accordance with unified standards and norms. SOP stage refers to the stage of formulating and implementing standard operating procedures in the operation of enterprises or organizations. By formulating SOP, enterprises can ensure that all aspects of work are carried out according to established standards, improve work efficiency, reduce error rate and ensure the consistency of product quality. The SOP stage includes formulating SOP documents, training employees, implementing SOP, and supervising and improving SOP. The goal of this stage is to make the operation of the enterprise more standardized and efficient, ensure that the work of all departments and posts can be carried out according to unified standards, and improve the overall management level and professional quality.