元数据（Metadata）被称为“关于数据的数据”，是为了帮助用户对网络信息资源实现有效、快速、准确的查找而产生的，“是一种用来描述数字化信息资源，特别是网络信息资源的基本特征及其相互关系，从而确保这些数字信息资源能够被计算机及其网络系统自动辨析、分解、提取和分 Metadata is referred to as “data about data” and is intended to help users search efficiently, quickly, and accurately for network information resources. "Metadata is a type of information used to describe digital information resources, especially network information The basic characteristics of resources and their mutual relations so as to ensure that these digital information resources can be automatically identified, decomposed, extracted and classified by computers and their network systems