When a person comes across the word “Radiotherapy”, it reminds him/her about the electric current. Some people may call the treatment as “Shock treatment” which is absolutely a myth. Radiotherapy is a form of cancer treatment using x-rays or gamma rays. The treatment is delivered by using a machine called “Linear Accelerator”. The treatment is given five days a week usually for a period of 4-6 weeks. It is a painless procedure and the side effects are minimal with the use of higher end techniques like IMRT, IGRT, Rapid Arc and SBRT. Radiotherapy can be given before surgery (neo-adjuvant), after surgery (adjuvant) or can be given with chemotherapy (concurrent chemo radiotherapy) in order to avoid surgery. In some patients it can be given to alleviate the symptoms of cancer like pain, bleeding, etc., where it is called as palliative radiation. Some of the non-cancerous conditions can also be treated with radiotherapy. With the advancements in the technology, the treatment is so precise that it targets only the tumor cells, causing very minimal damage to the normal tissues. In the modern era, radiation along with chemotherapy can help patients in avoiding surgery thereby helping in organ (function) preservation which in turn helps the patients to have good cosmetic outcome and better quality of life. This is especially seen in throat cancer where surgery will entail removal of the windpipe and loss of voice where radiotherapy can cure the disease without the need of removal of windpipe. In early breast cancer patients, if the tumor alone is removed (lumpectomy), radiation can prevent the disease coming back in the primary tumor site thereby giving good cosmetic outcome. In gynecological malignancies especially cancer cervix, it alleviates the need of morbid surgery. In early throat cancer patients, radiation alone can cure the disease avoiding the need of chemotherapy as well as surgery with very minimal side effects. The dryness of mouth (xerostomia) a common side effect of radiotherapy in head & neck cancers can be minimized by using “parotid salivary gland sparing” technique. The dose to the heart and its vessels (coronary arteries) especially in left sided breast cancer patients can be reduced by using “breath hold” technique and “cardiac sparing” technique. The cancer in the lung and in the liver can be accurately targeted and treated by using “gating” technique. In pelvic malignancies, the dose to the bladder and the bowel can be minimized using protocol based radiotherapy. In early prostate cancer patients, the total treatment time can be reduced to 1-2 weeks using “SBRT technique” as against 6-7 weeks’ treatment using “conventional technique”. In patients with cancer which have spread to brain, use of “SRS & SRT “techniques (hippocampal sparing) can reduce the duration of treatment from 12 days to 5 days’ maximum with preservation of memory and other higher mental functions. From the above, one can come to a conclusion that radiotherapy is a real boon to cancer patients by giving good chance to get cured with minimal side effects, good cosmetic outcome and better quality of life.