Method of representing the three-dimensional structures of molecule s on a page, devised by Emil Fischer .
By convention, horizontal lines represent bonds projecting from the plane of the paper toward the viewer, and vertical lines represent bonds projecting away from the viewer. Fischer projections are a convenient way to depict chiral molecules (see optical activity ) and distinguish between pairs of enantiomers (see racemate ). They are most often used to depict isomer s of the sugar s. See also chemical formula .