Residual files are pieces of information that are generally not accessible through the operating system and typically require special software for removal. This data comes from files that have been deleted but not completely erased. When you uninstall an application, residual files often remain on your system.

To maintain good PC performance, you need to delete residual files on your Windows PC regularly. If these residual files are not cleaned up on time, they will accumulate, which may eventually cause low disk space.