In humans, there are 12 pairs of ribs. Each rib has its dorsal attachment to the vertebral column and ventral attachment to the sternum. Depending on this attachment the ribs are categorised into three types. The first seven pairs are called true ribs or the vertebro-sternal ribs due to their direct attachment to the sternum ventrally. The 8th,9th and 10th pair is called the false ribs or the vertebro-chondral ribs due to their indirect attachment to the sternum via the costal cartilages of the ribs above them and the last two pairs (11th and 12th) are not connected ventrally and are known as floating ribs.