Booklet 1 of the series of publications is intended for all those who want to delve into the topic of light and lighting or wish to familiarize themselves with the basics of lighting technology. It also forms the introduction to a series of publications designed to provide useful information on lighting applications for all those involved in planning or decision-making in the field of lighting. One of the principal objectives of all publications is to promote awareness of a medium which we generally take for granted and use without a second thought. It is only when we get involved in “making” light, in creating artificial lighting systems, that things get more difficult, more technical