DNIX is a discontinued Unix-like real-time operating system from the Swedish company Dataindustrier AB (DIAB). A version named ABCenix was developed for the ABC 1600 computer from Luxor. Daisy Systems also had a system named Daisy DNIX on some of their computer-aided design (CAD) workstations. It was unrelated to DIAB's product.

Dataindustrier AB or DIAB was a Swedish computer engineering and manufacturing firm, founded in 1970 by Lars Karlsson and active in the 1970s through 1990s. The company's first product was a board-based computer centered on a specific bus named Data Board 4680. This unit was used for automatic control in several Swedish industries as would be almost all of DIAB's computers. DIAB is mostly known for engineering the ABC 80, the first Swedish home computer, manufactured by Luxor AB.