What is a massive, room-sized computer that process and store enormous amounts of bulk data and information?

Mainframe Computer

Explanation:

The Mainframe Computers are designed for bulk data processing with high speed and storing huge data that can't be performed by other regular PCs. They can run multiple instances of operating systems at the same time. They are used for application such as accounting, business transaction, information retrieval, airlines for the seat reservation and engineering computation.