Plan 9 from Bell Labs is a distributed operating system originally developed by Bell Labs and now open source. Plan 9 builds upon Unix concepts, and targets the general computing and research markets. The final official release, version 4, was finalised in 2015 - however the OS has been ported across many platforms and a handful of derivatives exist. With development initiated in the late 1980s, Plan 9 "demonstrates a cleaner way" to work an operating system, tightly integrating the then-new Internet into a unified communications protocol, known as the 9P Protocol. The 9P Protocol extends the Unix "everything is a file" model into local, network, and inter-process communications, removing the need for specialised APIs. Thus, the Unix influence feels "familiar" but "quite foreign." Files are even used to manage processes and interfacing with networking hardware - one can cd into the /proc folder and use file system tools to view processes running on their system. A union file system is also available, allowing complex applications of Plan 9. Additionally, beginning in 1992, Unicode is natively implemented. Another artifact from being developed many decades after Unix is that Plan 9 delivers a hyperlinked GUI out-of-the-box and by default. rio uses a system of windows, treated as text, to allow the user to run software. However, Unix compatibility was not intended and is poor. Ultimately, Plan 9 has suffered from low adoption due to the general lack of software and drivers as a result of it's ambitious approach.