In sock terms, ribbed is the most popular construction. This standard sock construction is well-known because it has visual and tactile appeal. It also gives extra elasticity to the sock. These are knit on a double cylinder.
Ribbing is the vertical profile of the weave known as the rib. Socks can be knit in various rib patterns for either styling or function. A rib can be composed of one or more rows of stitches. To determine the rib construction of a sock, you have to stretch it slightly as it would be on the foot and the ribs will show.