A sutura, or suture, is a type of fibrous joint found in the skull. It connects the bones of the skull together, allowing for slight movement during growth and development. Sutures are important for protecting the brain and providing structure to the head. As a person ages, sutures can become less flexible and may even fuse completely, a process known as suture fusion. This can affect the shape of the skull and is a normal part of aging. Sutures are also significant in craniosynostosis, a condition where one or more sutures close prematurely, potentially leading to developmental issues.