AROS is based on concepts and ideas of the “Amiga”, a computersystem of the early 90s based on the 68000 processor family. But AROS is not a emulation or just a retro-system, it is a modern opensource OS that inherits the concepts and ideas and brings it to today. It is a community project, everyone working free of charge and just for fun for it. There are different hardware supported, including X86, ARM, PPC and 68k. There are no emulation layers but it is really compiled for the specific hardware and thus running at full speed (the only exception is the 68k version that also can run in emulation). All versions inherit efficiency so AROS is one of the fastest OS existing and even running on older hardware very efficient.
Why starting with AROS?
Short: It is fun. AROS is opensource, so everyone can take part, f.e. develop at AROS, drivers, applications and games, port software, help to test, donate to support the developers and so on. Nobody is forced to but everyone can get involved.
It is certainly not yet good enough for everyday use and for the typical average users but it is perfect for former amiga-user and people that are interested in alternatives. There are new developments like AEROS, native version for Raspberry PI and dedicated hardware becoming ready and offering opportunities for Indy game developers to get early in a new and growing market.
On the gaming side there are already thousands of games for 68k and X86 available. You can either download and use “AROS Vision” (68k) or use Icaros Desktop or AEROS that both include 68k emulation.