BeOS

BeOS is a discontinued operating system, first developed by Be Inc. in 1991. It was developed to run on the PowerPC-based BeBox hardware, and ported to x86 for version 3. It was designed for multimedia applications. BeOS is POSIX-compatible but not UNIX-derived. After its discontinuation, the community is making a new operating system named Haiku, using BeOS concepts.

BeOS in emulators
The operating system is notorious for its usage of install media with multiple tracks. This makes it harder to install it in virtualization software, as converting the disc image to a format designed to only store a single track such as ISO 9660 will result in a boot error. Some tools are also known to convert the image into a multi-track format consumable by a VM, although they discard the track information in the process and write a cue file with a single track, leading to the same error.