The anchor chain – also known as marine chain – is a classic style that features uniformly sized repeating oval links with or without a vertical bar in the middle of each link.
Photo Courtesy of Chopard

The French rope chain is made of machine-flattened wire with each wire link woven into the next one.
Photo Courtesy of Boucheron 

The link chain – also known as cable chain – is the most common of chain types. It is formed of individual round or oval links interlocked in a uniform pattern with each link lying at 90 degrees to the next.
Photo Courtesy of Bulgari

The trace chain is usually a fine and delicate one that uses small and slightly oval links.
Photo Courtesy of de Grisogono

The Rolo chain – also known as belcher chain or baby belcher chain according to its thickness – is made of alternating round and oval links.
Photo Courtesy of Van Cleef & Arpels