Affine coordinates are a system used in geometry to describe points in a space relative to a set of reference points, known as affine basis. In this system, each point is represented as a linear combination of these basis points, allowing for easy manipulation and transformation of shapes. This method is particularly useful in computer graphics and geometric modeling. In affine coordinates, the relationships between points are preserved, meaning that parallel lines remain parallel and ratios of distances are maintained. This property makes affine coordinates valuable in various applications, including computer-aided design and robotics, where accurate representation and transformation of shapes are essential.