Intramembranous Ossification is a process by which bone tissue forms directly from mesenchymal tissue, which is a type of connective tissue. This method primarily occurs in the development of flat bones, such as those in the skull and the clavicle. During this process, mesenchymal cells differentiate into osteoblasts, which are cells responsible for bone formation. As the osteoblasts produce bone matrix, they become trapped in the matrix and transform into osteocytes, which help maintain the bone. Over time, this process leads to the formation of a dense, solid bone structure. Intramembranous ossification is crucial for the initial formation of the skeleton and for the healing of bone fractures.