Learn in the textbookTypes and Characteristics of Computers
DefinitionA general-purpose computer (mainframe, 汎用コンピュータ / メインフレーム) is a large computer that supports the core business of companies and government offices.
ExplanationIt has the processing power and reliability to work through large volumes of data for long periods without stopping, and is used for work that cannot halt, such as managing bank accounts. The "general-purpose" in its name means it is not limited to one kind of calculation but can run all sorts of business work.
AnalogyIt is like a large power plant that keeps the whole town supplied with electricity.
Memory hookThe Japanese 汎 means "broadly", so 汎用 reads as "broadly used", the same idea as general-purpose.