Mainframe systems 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 mission-critical operations. These systems often run specialized operating systems, such as z/OS, and can support various programming languages. Mainframes are known for their ability to perform complex calculations quickly and efficiently, making them ideal for tasks like data processing and financial transactions. Their architecture allows for high levels of redundancy and fault tolerance.