Projection, projections or projective may refer to:

Physics

* Projection (physics), the action/process of light, heat, or sound reflecting from a surface to another in a different direction * The display of images by a projector

Optics, graphics, and cartography

* Map projection, reducing the surface of a three-dimensional planet to a flat map * Graphical projection, the production of a two-dimensional image of a three-dimensional object

Chemistry

* Fischer projection, a two-dimensional representation of a three-dimensional organic molecule * Haworth projection, a way of writing a structural formula to represent the cyclic structure of monosaccharides * Natta projection, a way to depict molecules with complete stereochemistry in two dimensions in a skeletal formula * Newman projection, a visual representation of a chemical bond from front to back

Mathematics

* Projection (mathematics), any of several different types of geometrical mappings ** Projection (linear algebra), a linear transformation from a vector space to itself such that ** 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), a type of unary operation in relational algebra * Projective geometry, the study of geometric properties that are invariant with respect to projective transformations * Projective module, a generalization of a free module * Projective object, a further generalization, in category theory * Projection method (fluid dynamics), means of numerically solving time-dependent incompressible fluid-flow problems

Biology

* Projection areas, areas of the brain where sensory processing occurs * Projection fiber, in neuroscience, white matter fibers that connect the cortex to the lower parts of the brain or the spinal cord

Linguistics

* Projection (linguistics), grammatical trait inheritance from a head to a phrasal category * Projection principle in syntax * Projection of presuppositions in linguistics

Arts and entertainment

* Projections (Star Trek: Voyager), "Projections" (''Star Trek: Voyager''), an episode of the television series ''Star Trek: Voyager'' * Projections (The Blues Project album), ''Projections'' (The Blues Project album), 1966 * Projections (John Handy album), ''Projections'' (John Handy album), 1968 * Projections (film), ''Projections'' (film), 2013 Croatian film

Other uses

* Projection (alchemy), process in Alchemy * Projections (journal), ''Projections'' (journal), an interdisciplinary academic journal related to cinema and visual media * Power projection, the capacity of a state to implement policy by means of force, or the threat thereof * Psychological projection, or "Freudian projection", a defense mechanism in which one attributes to others one's own unacceptable or unwanted attributes, thoughts, or emotions *Social projection, a cognitive bias that leads people to believe others are similar to themselves * Forecasting, making predictions of the future based on past and present data