st-ro is based on open-source design, emulator for Ragnarok Online Server written in the C programming language and in control using SVN [Credit: rAthena (Base Core System), 3ceAM, Hercules, 3ceAM-v2, brAthena]. st-ro itself is a project that uses the Taiwan servers in the core, scripts, and his client base and can run several operating systems that exist today.