Learn in the textbookDatabase and DBMS Basics, and Types of NoSQL
DefinitionA database (データベース) is a collection of data organized for a purpose and stored so that many users and applications can share it.
ExplanationIf each department keeps the same customer details in its own separate files, one copy may get a new address while the other does not, and the two disagree. Gathering the data in one place and organizing it cuts duplication and lets everyone see the same up-to-date content.
AnalogyIt is like keeping one shared address book in the living room instead of each family member writing contacts in a personal notebook. When someone updates it, everyone sees the same entries.
Memory hookRead the word literally: the "base" where data is gathered and kept.