Traumatic Brain Injury (TBI) is a blow or jolt to the head or a penetrating head injury that disrupts the function of the brain. Each year there are a reported 1.7 million brain injuries in the United States, and an estimated 5.3 million Americans â€” about 2 percent of the U.S. population â€” currently have a long-term or lifelong need for help with everyday activities due to TBI. Most brain injuries are mild and are also known as concussions. Usually people recover from a concussion in a matter of weeks but sometimes symptoms can persist. BrainLine.org, a free educational website, provides authoritative information about brain injury symptoms, diagnosis, and treatment. For people living with a brain injury, their families, and professionals in the field, BrainLine also offers an online community of support through our social networking sites.