Database is a structured collection of records or data. According to Michael V. Mannino , it is language and graphical tools to define entities, relationships, integrity constraints, and authorization rights. It acts as persistent data storage where particular data can later be retrieved easily from it. The organization of stored data itself relies on software. Compared to manually searching for particular data or files in our file holder, searching in database is much faster and handier, especially when it comes to searching through lots of data. Moreover, keeping data in database is more secure than keeping data in a file since the user will have to get through the database application before he/ she can view or use the data.
Regarding characteristic, database has several properties:
Persistent means that data are stored in persistent or stable storage, such as a Hard Disk, Floppy Disk, or Compact Disc (CD), so that the stored data will still be there even after the program has been terminated. Thus, data will be available when user later wants to get it when he/ she run the program on another occasion. However, it doesn’t mean that the data will last forever
inside the database. In some occasion when the data is no longer needed, the user can remove or delete the data from the database. Moreover, in another occasion when data is no longer valid, the user can get the data from the database, update it, and store it back into the database.
Shared means that database can be used for multiple purposes and can serve multiple users. Thus, data that resides inside the database can be shared among many users. However, when it comes to changing a particular data, only one user may have access to the data.
Interrelated means that data are stored as separate units inside the database, but it can be connected to assemble information. To ensure that the database is providing meaningful information, integrity rules are applied. In addition, data consistency is also preserved in order to provide valid and up-to-date information.
 M.V. Michael , “Introduction to Database Management” Database Design, Application Development, & Administration, second edition, pp. 3-22.