Welcome back to the RadOnc Smart Review Physics Series! Last episode, P4, we learned how kV X-rays are produced in tubes. Today, we're powering up significantly in Episode P5: High Energy Treatment Machines. We'll explore the historical Cobalt-60 units and then spend most of our time dissecting the modern workhorse of radiation oncology: the Linear Accelerator, or LINAC. We'll journey through its complex components, from generating electrons to shaping the final treatment beam.