Radiation that can penetrate human skin and is utilized in cancer treatment includes X-rays and gamma rays. These forms of electromagnetic radiation are effective because they have high energy levels capable of damaging the DNA of cancer cells, which disrupts their ability to grow and reproduce. While these radiant forms can also affect surrounding healthy tissues, medical professionals use precise targeting techniques to minimize damage. The controlled application of radiation therapy aims to shrink tumors and manage various types of cancer effectively, showcasing the balance between treatment efficacy and safety.