Mainframes are powerful computers designed to handle large volumes of data and support numerous users simultaneously. They are commonly used by large organizations, such as banks and government agencies, to process transactions, manage databases, and run critical applications. Their reliability, scalability, and security make them essential for operations that require high availability. These systems are known for their ability to run multiple operating systems and applications at once, often using virtualization technology. Mainframes can efficiently manage workloads and ensure data integrity, making them a preferred choice for industries that rely on big data, cloud computing, and enterprise resource planning (ERP) systems.