Orbit refers to the sunken part of human or animal skull where the eyeball is embedded. It is a complex bone structure composed of orbital bone, frontal bone, zygomatic bone, lacrimal bone and ethmoid bone. The main function of the orbit is to protect the eyeball, and at the same time, it can make the eyeball move within a certain range, ensuring that people and animals can see the surrounding environment clearly.

The origin of orbit can be traced back to ancient humans, and the earliest fossilized orbit can be traced back to the ancestor monkey about 30 million years ago. In the process of evolution, the shape of the orbit gradually evolved, adapting to the different living environments and lifestyles of people and animals. For example, Nocturnal Animals's eyes are bigger, and his eyes are enlarged accordingly to enhance his vision in the dark. In the process of human evolution, the shape of the orbit has also undergone a long change, such as thickening of the orbital margin, enlargement of the orbit and deepening of the orbital floor.

Besides biological significance, orbit is also of great significance in the medical field. Doctors can judge people's health by observing and checking the shape, size and depth of the orbit, and carry out related treatment. At the same time, in ophthalmic surgery, doctors also need to operate the orbit accurately to ensure the success rate and safety of the operation.