Error-correcting codes are techniques used in digital communication and data storage to detect and correct errors that may occur during transmission or retrieval. These codes add extra bits to the original data, allowing the system to identify and fix mistakes without needing to resend the information. When data is sent over a network or stored on a device, it can become corrupted due to noise or other interferences. Error-correcting codes work by using algorithms that analyze the received data, compare it to the expected format, and make necessary adjustments. This ensures that the information remains accurate and reliable.