Forward head posture occurs when the head juts forward of the torso's midline. It involves upper neck extension and lower neck flexion, flattening the normal cervical curve. Common causes include excessive smartphone, computer, and driving time. Symptoms may include neck, shoulder, and head muscle pain. Diagnosis involves tests like the wall test and side profile photos. Treatment focuses on strengthening weak neck muscles and stretching tight ones, along with ergonomic adjustments.