This chapter is concerned with defining and describing the substantive content of this book, namely two-dimensional abstract art from the last 115 years. This chapter also sets the scene for the philosophical and psychological research I present later in this book. In defining abstract painting and drawing, I draw upon my own experiences of viewing this art form and then review the writing of several scholars and critics. I also consider abstraction as the contrast of representationalist painting and I introduce the writing of philosopher Paul Crowther and his eight characteristics of an artwork that typify a piece of art as being an abstract artwork. As well as abstraction, other forms of art and art in general are considered in my attempt to clearly delineate the focus of this research.