Cervical precancers are categorized into different stages based on the severity of the abnormal cell changes. These stages are known as Cervical Intraepithelial Neoplasia (CIN) and are classified as CIN1, CIN2, and CIN3. CIN1 represents mild changes, CIN2 signifies moderate changes, and CIN3 indicates severe changes that are most likely to progress to cancer if untreated.