Editing Projection (section)

==Mathematics==
* [[Projection (mathematics)]], any of several different types of geometrical mappings
** [[Projection (linear algebra)]], a linear transformation {{mvar|P}} from a vector space to itself such that {{math|1=''P''<sup>2</sup> = ''P''}}
** [[Projection (set theory)]], one of two closely related types of functions or operations in set theory
** [[Projection (measure theory)]], use of a projection map in measure theory
** [[3D projection]], any method of mapping three-dimensional points to a two-dimensional plane
** [[Vector projection]], orthogonal projection of a vector onto a straight line
** [[Projection (relational algebra)]]<!-- This item used only in a very specialized area, thus, please, keep it at the end -->, a type of unary operation in relational algebra
* [[Projection method (fluid dynamics)]], means of numerically solving time-dependent incompressible fluid-flow problems