The United Nations General Assembly proclaimed 2015 as the International Year of Light (IYL 2015). The IYL was to recognize the tremendous applications of light in our everyday lives: from the benefits of sunlight, to the intricate processes in our eyes, to holography, to fiber optic communications across oceans, to extremely important applications of lasers from eye surgery to drilling holes in steel and to numerous other areas. From its inception, The National Academy of Sciences, India (the oldest Science Academy in India) is committed to bringing scientific developments to the benefit of the society at large. Keeping this in mind, and as a part of the celebration of IYL 2015, the Academy entrusted the editors to bring out a book in which various aspects of light and light-based technologies will be lucidly described by experts with the aim to enthuse young students, teachers and the general public to get interested in studying more about light and be aware of its phenomenal applications. The editors were very fortunate to get a large number of experts to agree to contribute to this book. Of course, there are many other very interesting areas which could have been covered.
We hope that the book will be able to enthuse the younger generation to study more about light.