Normal (geometry) Normal (geometry) In geometry, a normal is an object such as a line or vector that is perpendicular to a given object. For example, in two dimensions, the normal line to a curve at a given point is the line perpendicular to the tangent line to the curve at the point. In three dimensions, a surface normal, or simply normal, to a surface at a point "P" is a vector that is perpendicular to the tangent plane to that surface at "P". The word "normal" is also used as an adjective: a line normal to a plane, the normal component
This is Not a Book This is Not a Book This is Not a Book is a book by Keri Smith that was published in 2009. It is not a normal book, because the book does not exist without the reader. The book is almost completely blank, so the reader creates the content and the final product. The book's purpose is to teach a reader to think creatively and take risks. The main question presented is: if it is not a book, then what exactly is it? The answer is left to the reader to determine. "This Is Not A Book" is much like Wreck