Manufacturing data is heterogeneous information systematically collected or generated throughout the manufacturing lifecycle, encompassing diverse sources such as sensor readings, operational logs, quality metrics, and supply chain records. As a research concept and field, it investigates patterns, relationships, and anomalies within production systems to enable the optimization of processes, enhancement of product quality, prediction of maintenance needs, and improvement of overall manufacturing efficiency, forming a critical foundation for data-driven decision-making and advanced manufacturing paradigms.