The means by which the information on a microfiche is retrieved. There are several indexing techniques available today. These includecorner indexing, column indexing, master-file indexing, and cross-reference indexing.; 檢索縮微膠片上信息的方法。目前有多種索引技術(shù),包括邊緣索引、列索引、主文件索引和交叉引用索引。