The two ribs often refer to the twelve pairs of ribs on both sides of the chest, consisting of ribs and costal cartilage, with the role of forming the thorax and maintaining the integrity of the thorax. 1. There are 24 ribs in total, symmetrically distributed on both sides, totaling 12 pairs. Generally speaking, the first to seventh ribs are directly connected to the sternum and are called true ribs, while the last 8 to 10 ribs are called false ribs because they are not directly connected to the ribs. The remaining two pairs of ribs are free at the front end and are called floating ribs. 2. The costal cartilage is composed of hyaline cartilage, which is located at the anterior end of each rib and does not ossify throughout life. 3. Ribs and sternum, thoracic vertebrae and their connections together form the thorax, which is important for maintaining the integrity and stability of the thorax. At the same time, it also protects the heart, lungs and other important thoracic organs and participates in respiratory movement. The two ribs are very important parts of the human body. In case of injury or lesion, you should go to the hospital in time.