How to build an efficient tagging system for blogs

What are Tags? In simple terms, it is a bidirectional multiple mapping between blog Posts and Keywords. Posts and Tags can be tagged multiple times depending on the content. Click on a tag to view multiple posts related to it. The traditional classification is generally single-attribute, folder type. The Categories category in WordPress also has such multiple attributes and can actually perform the same function. My approach is to use categories to divide categories, and use labels to label content keywords. This builds a content-related network that relies on tags, allows readers to easily jump between their favorite content, and is very friendly to search engines.