Cancer is a disease that occurs when cells in the body begin to grow out of control. There are many different types of cancer, each with its own set of symptoms. Some common symptoms of cancer include:

1. Unexplained weight loss: Losing weight without trying can be a symptom of many types of cancer, including pancreatic, stomach, lung, and ovarian cancer.

2. Fatigue: Feeling tired and weak all the time can be a symptom of many types of cancer, especially in the early stages of the disease.

3. Pain: Pain that doesn't go away, especially if it's in a specific area of the body, can be a symptom of many types of cancer, including bone cancer, brain cancer, and ovarian cancer.

4. Skin changes: Changes in the skin, such as darkening, yellowing, or redness, can be a symptom of skin cancer.

5. Changes in bowel or bladder habits: Changes in bowel or bladder habits, such as constipation, diarrhea, or blood in the urine, can be a symptom of colon, bladder, or kidney cancer.

6. Sores that don't heal: Sores that don't heal can be a symptom of skin cancer or oral cancer.

7. Difficulty swallowing: Difficulty swallowing can be a symptom of throat or esophageal cancer.

8. Persistent cough: A persistent cough that doesn't go away can be a symptom of lung cancer.

9. Lump or swelling: A lump or swelling in any part of the body can be a symptom of cancer, including breast cancer, testicular cancer, and lymphoma.

10. Fever: A fever that doesn't go away can be a symptom of some types of cancer, especially leukemia and lymphoma.

It's important to remember that these symptoms can also be caused by other conditions that are not cancer, so it's important to see a doctor if you are experiencing any of them. If cancer is detected early, it is often easier to treat and has a better chance of being cured