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 civilian brain injuries in the United States. In the military between 2000 and the fourth quarter of 2011, more than 230,000 service members sustained a TBI. Brain injury, caused largely by improvised explosive devices (IEDs), has become the signature wound of the wars in Iraq and Afghanistan. Most brain injuries are mild, and most people recover in a matter of weeks. BrainLineMilitary.org provides military-specific information and resources on traumatic brain injury to veterans; service members in the Army, Navy, Air Force, Marines, National Guard, and Reserve; and their families.