Molecule of butane in syn-clinal (-sc) conformation
Sawhorse projection
Newman projection
A Newman projection, useful in alkane stereochemistry, visualizes chemical conformations of a carbon-carbon chemical bond from front to back, with the front carbon represented by a dot and the back carbon as a circle (see below). The front carbon atom is called proximal, while the back atom is called distal. This type of representation is useful for assessing the torsional angle between bonds.
A Sawhorse representation, on the other hand, views a carbon-carbon bond from an oblique angle. This type of representation makes it easy to visualize the molecule as a whole in 3-D.