Be was ultimately unable to achieve a significant market share and ended development with dwindling finances, so Palm acquired the BeOS assets in 2001.

Enthusiasts have since created derivate operating systems including Haiku, which will retain BeOS 5 compatibility as of Release R1.

Development began in the early 1990s, initially designed to run on AT&T Hobbit-based hardware before being modified to run on PowerPC-based processors: first Be's own BeBox system, and later Apple Computer's PowerPC Reference Platform and Common Hardware Reference Platform, with the hope that Apple would purchase or license BeOS as a replacement for its aging Mac OS.

[12] Release 3 (R3) shipped in March 1998 (initially $69.95, later $99.95), as the first to be ported to the Intel x86 platform in addition to PowerPC, and the first commercially available version of BeOS.

[13] The adoption of x86 was partly due to Apple's moves, with Steve Jobs stopping the Macintosh clone market,[14] and Be's mounting debt.

[21] Be CEO Gassée said in 2001 that he was open to the idea of releasing the entire operating system's source code,[22] but this never materialized.

[25] (Advanced Access Preview Release) Personal Edition/Pro Edition After the discontinuation of the BeBox in January 1997, Power Computing began bundling BeOS (on a CD-ROM for optional installation) with its line of PowerPC-based Macintosh clones.

[31] BeOS was developed as an original product, with a proprietary kernel, symmetric multiprocessing, preemptive multitasking, and pervasive multithreading.

[17] BeOS has partial POSIX compatibility and a command-line interface through Bash, although internally it is not a Unix-derived operating system.

[37] Be operated the marketplace site BeDepot for the purchase and downloading of software including third party, and a website named BeWare listing apps for the platform.

[41] Be did not disclose the number of BeOS users, but it was estimated to be running on between 50,000 and 100,000 computers in 1999,[30] and Release 5 reportedly had over one million downloads.

[18] For a time it was viewed as a viable competitor to Mac OS and Windows, but its status as the "alternative operating system" was quickly surpassed by Linux by 1998.

[42] Reception of the operating system was largely positive citing its true and "reliable" multitasking and support for multiple processors.

[45] BeOS received significant interest in Japan,[11] and was also appealing to Amiga developers and users, who were looking for a newer platform.

[54] Magicbox, a manufacturer of signage and broadcast display machines, uses BeOS to power their Aavelin product line.

[55] Final Scratch, a 12-inch vinyl timecode record-driven DJ software and hardware system, was first developed on BeOS.

[61] Immediately after Palm's purchase of Be, a German company named yellowTAB started developing Zeta based on the BeOS R5.1 codebase and released it commercially.

[64] BlueEyedOS tried to create a system under LGPL based on the Linux kernel and an X server that is compatible with BeOS.