What is time? What do we understand when we think about time? What do we mean by ‘now’? This book covers concisely all the different aspects of time with an anchoring point within the geological sciences. Here successions of strata are seen as representing successions of events in the long history of the earth; palaeontology provides a record of organic evolution through nearly the whole of these several thousand million years. The rest of the book diversifies in discussing the measurement of time both physically and biologically; our human perception of it; the ending of personal time in death; the pervading presence of time in the arts; out through astronomy to cosmology; into philosophy and religion. The idea of time is a very complex one but this book undertakes a journey to prove that it is not beyond comprehension.