In chemistry, a Fischer projection is a two-dimensional representation of a three-dimensional organic molecule devised by Emil Fischer in 1891. Fischer projections depict the stereochemistry of molecules and are thus useful for depicting enantiomers of chiral molecules, especially monosaccharides. The carbon backbone of the molecule is depicted as a vertical line and the bonds of side chains are represented as horizontal lines, with carbon atoms represented by the center of crossing lines. The orientation of the carbon chain is such that the C1 carbon is at the top of the molecule diagrammed. Vertical lines lie either in or behind the plane of the paper, while horizontal lines project out from the surface. In a Fischer projection, the plane of symmetry (3D) between two enantiomers becomes a line of symmetry between their 2D representations.