This file appears to be a compressed archive containing custom scenery or orthophotos for X-Plane 11 , focusing on the region of Taiwan.
did you download the file from (e.g., a specific forum, file-sharing site)? taiwan-xp11.rar
As with any .rar or .zip file downloaded from third-party sources or community forums, it is strongly advised to scan the file with updated antivirus software before extracting it. This file appears to be a compressed archive
Files with this naming convention are generally distributed via flight simulation community forums (such as X-Plane.org), specialized scenery websites, or file-sharing platforms. Key Considerations a specific forum
It is likely designed to enhance the default X-Plane 11 environment with improved terrain, textures, or landmarks for the area [1].