Inferno is a distributed operating system started at Bell Labs and now developed and maintained by Vita Nuova Holdings as free software under the MIT License.

The name of the operating system, many of its associated programs, and that of the current company, were inspired by Dante Alighieri's Divine Comedy.

Inferno was created in 1995 by members of Bell Labs' Computer Science Research division to bring ideas derived from their previous operating system, Plan 9 from Bell Labs, to a wider range of devices and networks.

It defines a virtual machine, known as Dis, that can be implemented on any real machine, provides Limbo, a type-safe language that is compiled to portable byte code, and, more significantly, it includes a virtual operating system that supplies the same interfaces whether Inferno runs natively on hardware or runs as a user program on top of another operating system.

As of the fourth edition of Inferno, Styx is identical to Plan 9's newer version of its hallmark 9P protocol, 9P2000.

[13] Inferno is a descendant of Plan 9 from Bell Labs, and shares many design concepts and even source code in the kernel, particularly around devices and the Styx/9P2000 protocol.

At the same time, Bell Labs' parent company AT&T licensed Java technology from Sun Microsystems.

The advertisement stated that video games could talk to computers,–a PlayStation was pictured–cell phones could access email and voice mail was available via TV.

During the same time Sun Microsystems was heavily marketing its own Java programming language, which was targeting a similar market, with analogous technology, that worked in web browsers and also filled the demand for object-oriented languages popular at that time.

The Inferno Business Unit closed after three years, and was sold to Vita Nuova Holdings.