"External beam radiation therapy (EBRT) (also known as teletherapy) is a form of ionising radiation therapy delivered by a medical linear accelerator (or historically a cobalt-60 source) to a patient lying on a treatment bed. Megavoltage x-rays (4-25 MV) are the most commonly used. Alternative forms of EBRT include electron therapy, orthovoltage x-rays (0.1-1 MV), and particle therapy (proton therapy, neutron therapy, and carbon ion therapy)."
"There are many types of external beam radiation therapy 1-5:"