What are the different types of rib bones that form the rib cage?

Explanation

There are 12 pairs of ribs. Each rib is thin flat bone connected dorsally to the vetebral column and ventrally to the sternum. It has two articulation surfaces on its dorsal end, hence called bicephalic.
True ribs:
The first seven pairs of ribs are called 'true ribs' or vertebro-sternal ribs. Dorsally they are attached to the thoracic vertebrae and ventrally connected to the sternum with the help of hyaline cartilages.
False ribs:
The 8th, 9th and 10th pairs of ribs do not articulate directly with the sternum but joined with the cartilaginous (hyaline cartilage) part of the seventh rib. These are called 'false ribs' or vertebro-chondral ribs.
Floating ribs:
The last 11th and 12th pairs of ribs are not connected ventrally. Therefore, they are called as 'Floating ribs' or vertebral ribs.
Formation of rib cage :
1. Thoracic vertebrae, ribs and stemum together form the ribcage.
2. Rib cage protects the lungs, heart, liver and also plays a role in breathing.