This file extension is currently used in three different ways:  being primarily associated with Microsoft Corporation for its Windows systems as in the file Thumbs.DB,  as a Borland Paradox database file and  as a generic database file which is why it is called DB, meaning DataBase. Therefore, files with a DB file extension are commonly associated with database files and are usually hidden in system directories.
DB files are typically created by different database software or applications that are supported by the appropriate operating system where the application operates. There are several and different data that are accumulated and contained in files with this file extension making it one of the most useful file extensions ever created. Most of these data are critical to a computer system and even for a business.
A DB file (Thumbs.DB) in a Windows operating system is always associated with a certain program installed in the system. The link between Windows, the specific application and the DB file is managed by Windows Registry and therefore crucial in Windows.
Generic database files however are usually created with a structured format that makes it easier to store data critical for some businesses. This structure is usually made up of tables, fields, values, data types and many more and can be generated through different database applications.
Aside from the opening DB files, some database applications can export a DB file into different formats as well like CSV (comma separated values) and many more. Below is the list of these different applications:
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