Cancer staging is a system used by doctors to determine the extent of cancer in a patient's body. It helps classify the cancer based on its size, location, and whether it has spread to nearby lymph nodes or other organs. The most common staging system is the TNM system, which stands for Tumor size, Node involvement, and Metastasis. Staging is crucial for developing a treatment plan and predicting the patient's prognosis. Early-stage cancers are generally easier to treat and have a better chance of recovery, while advanced-stage cancers may require more aggressive therapies. Understanding the stage of cancer helps guide both patients and healthcare providers in making informed decisions.