This book has been written by nearly twenty relevant authors in the field of ionic liquids. This book is a summary which will appeal not only to students and professionals, but also to non-qualified people interested in chemistry in general. Certainly, the readers of this book can take a pleasant stroll through the marvellous world of ionic liquids and some of their most important and novel applications. Their characteristics and applications are presented from the most general to the most specific points of view. In addition, these points are presented with more than sufficient scientific and technical references which can easily be found in the literature.