AROS Research Operating System (AROS, pronounced "AR-OS") is a free and open-source multi media centric implementation of the AmigaOS 3.1 application programming interface (API). Designed to be portable and flexible. As of 2021, Ports are available for x86-based and PowerPC-based personal computers (PCs) in native and hosted flavors, with other architectures in development. In a show of full circle development, AROS was also ported to the Motorola 68000 series (m68k) based Amiga 1200, and there is also an ARM port for the Raspberry Pi series.