ROPLS™

In the Resident Evil Universe, Umbrella have their own Operating System (OS) which is used on virtually all computer systems from home systems to mainframes and supercomputers. In facilities, it is mainly used to control security devices, for example live CCTV monitoring, recording, electronic door and shutter locks, as well as support for smart card systems - but they can also be used for more general things such as viewing pictures, videos, reading documents and browsing the internet.

In the original Resident Evil and the Remake, it is known as Umbrella Computer OS ROPLS™. It's appearance varies throughout the series, but it appears to be based on a mixture of an older Apple OS (System 7) and an early Windows OS (Windows 3.1) but with more modern features such as on-screen keyboard, full colour display and anti-aliased text rendering.

What we do know is that it has an extremely fast boot sequence for the time, and used a rather unusual alphabetic ABCDEF style keyboard rather than the more common QWERTY. It supported user accounts with password protection. One such user on a system in the Spencer Mansion was JOHN, and the password was ADA (obviously from a time where account security was not a concern).

There is also a connected system which can Lock and Unlock doors in the Basement area of the Arklay Laboratory which runs as a simple command-line script. The password for opening them is MOLE.

In Resident Evil 2, both the Raccoon City Police Department and the NEST facility has computer systems with an OS called Umbrella "Rodem" System. This system appears to have the exact same functionality as ROPLS, albeit with a much more basic looking visual style. This is most likely the same OS, just an earlier incarnation.

It's not known what ROPLS stands for, although underneath the name just after the boot sequence it says 'Umbrella Computer OS Version 5.2.5' so it is most likely a pseudo-acronym.
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