Contact Sheets
What is a contact sheet?
A contact sheet is a positive print of all the negative images from one film, made by a contact printing process so that all the images are the same size as the negative. A contact sheet is a useful way of seeing which are the best images on a film so you can decide which ones to make enlargements from.
If there’s one thing photographers must never, ever do, it is to show their contact sheets or to display them in public. One must never show one’s contact sheets because they may prove too revealing, because wrong conclusions could be made and perhaps, and even worse, correct ones.
— Elliott Erwitt from the the DVD series Contacts