A mapping between two vector spaces that preserves vector addition and scalar multiplication is a fundamental concept in linear algebra. More formally, given vector spaces V and W over a field F, a transformation T: V W is considered to exhibit linearity if it satisfies the following two conditions: T(u + v) = T(u) + T(v) for all vectors u and v in V, and T(cv) = cT(v) for all vectors v in V and all scalars c in F. A typical example is a matrix multiplication, where a matrix acts on a vector to produce another vector, adhering to the principles of superposition and homogeneity.
This mathematical construct is vital because it allows for the simplification and analysis of complex systems by decomposing them into linear components. Its application extends across diverse fields such as physics, engineering, computer graphics, and economics, enabling solutions to problems involving systems that respond proportionally to their inputs. Historically, the systematic study of these transformations arose from the development of matrix algebra and the need to solve systems of linear equations efficiently.