This well argued book describes an interesting and counter-intuitive theory about the nature of truth. Horwich develops a 'minimal theory of truth' in which truth is not some weighty metaphysical entity but rather captured by simple statements like snow is white if and only if snow is white. Horwich argues that these simple equivalence relations capture all the crucial features of truth and how truth is used. This theory is essentially a descriptive account along the lines of a scientific theory. A possible analogy would be the use in Newtonian dynamics of concepts like mass. Like a concept such as mass, truth is an important property of propositions as a device to describe crucial features of the propositions but has little independent value when attempts are made to detach it form the items it is used to describe. For Horwich, truth is essentially a brute aspect of the world.
Much of this book is a fairly technical discussion of a number of challenges to the minimalist account and associated issues. Written for others in the field of epistemology, a good knowledge of the prior literature and formal logic is really needed to follow all the argument. Horwich is a good enough writer, however, that his text gives a good idea of his arguments.
As Horwich points out, this view has considerable implications for many areas of philosophy.