Compressed files like RARs are generally safe, but they can act as "wrappers" for malware. Before extracting, it is a good practice to scan the archive with your antivirus software. Never run an executable ( .exe ) file found inside an archive unless you are absolutely certain of its source.
: A popular, free, and open-source alternative found at 7-Zip.org .
: The official proprietary tool for this format, available at RARLAB .