Disk encryption is a security method that protects data stored on a computer's hard drive or other storage devices. It converts the information into a coded format, making it unreadable to unauthorized users. Only those with the correct decryption key or password can access the original data, ensuring that sensitive information remains secure. This technology is commonly used in laptops, smartphones, and external drives to safeguard personal and business data. If a device is lost or stolen, disk encryption helps prevent unauthorized access, reducing the risk of data breaches and identity theft.