In 2012, the School of Information and Library Studies at University College Dublin and Aer Lingus embarked on a collaborative project to develop a hybrid interactive digital archive for Aer Lingus material including photographs,posters, magazines, and oral histories. Part of Aer Lingus' proposed digital archive is a large number of unidentified photographs. The goal of this book is to facilitate user tagging and commentary on these photographs in order to identify the subjects (i.e., persons and events) for the navigation purposes of future users.