DBx

DBX is an acronym used in several unrelated domains, including computing, audio technology, and software tools. It does not denote a single product or standard, but rather different items that share the same abbreviation in their respective communities.

- Mailbox file format: In the Windows-era email client Outlook Express, messages were stored in mailbox files with the .dbx extension. Each folder had its own .dbx file (for example, Inbox.dbx). The format was widely used in Windows for basic mail storage, but modern email clients generally use alternative storage formats, and .dbx files are not typically read by current apps without conversion or third-party tools.

- Audio processing and noise reduction: The brand dbx (dbx, Inc.) produced audio processors and noise-reduction systems widely used in professional and consumer equipment. The company is known for technologies such as dbx noise reduction and various signal processing devices, including compressors and limiters. The dbx line has been influential in analog tape tooling and live sound, and the brand continues to appear in certain audio products.

- Unix debugger: dbx is a historical debugger for Unix-like operating systems. It provided interactive debugging capabilities, including setting breakpoints, inspecting variables, and tracing program execution. Over time, it was largely superseded in many environments by more contemporary debuggers such as gdb, but dbx remains a reference name in discussions of classic Unix development tools.

Overall, DBX encompasses multiple distinct concepts, with the most common references being Outlook Express mailbox storage, the dbx audio technology brand, and the Unix debugger.