Welcome back to RadOnc Smart Review, Physics Series! In P3, we saw how charged particles like electrons lose energy interacting with matter. Today, in Episode P4: kV X-ray Production, we harness those interactions! We'll focus specifically on how we generate kilovoltage (kV) X-rays, the kind used ubiquitously in diagnostic imaging (like CT and cone-beam CT) and historically in orthovoltage therapy. We'll dissect the X-ray tube and the physics behind creating those useful photons.