Check out this interactive stereochemistry tutorial on the ChemEdDL
Sawhorse diagrams are similar to wedge-dash diagrams, but without trying to use "shading" to denote the perspective. The representation to the right of propane has been drawn so that we are looking at the molecule, which is below us and to our left. Sawhorse diagrams are much less common than wedge-dash diagrams or Newman projections. Sawhorse diagrams are also used to view conformational isomers, much like Newman projections, but used much less frequently.