In SEO optimization, we often see long tail words, bidding words, index words, related words, drop-down words, associative words, etc. What are the meanings of these terms? What are the characteristics and how to collect, summarize and sort them out? 1. What is a long tail keyword? It is called a long tail keyword for short. It is a word that someone searches but the search volume is not high. It is generally a core keyword, a secondary keyword
