Young woman using the micofiche index at a London lending library. Microfiche is a microform storage medium in which images (in this application, book details; title, authors, subjects) are arranged in a grid pattern on a sheet of film, which contains an index or title that may be read without magnification. The user inserts the chosen sheet of microfiche into the viewer and manipulates its position until the relevant entry is found. Microfiche facilities have superceded traditional card index systems in many libraries.