Local options
WM Guard stores items such as settings, the access key, results from voluntary Witte Marketing actions, health history, the local change log, and notification comparison state in WordPress.
Temporary caches
Checksums, malware results, vulnerability results, DNS data, self-tests, and other technical results can be cached as WordPress transients.
On uninstall
When the plugin is deleted through WordPress, uninstall.php removes WM Guard’s own options, scheduled WM Guard cron events, and transients with the WM Guard prefix.
Difference: Simply deactivating the plugin does not delete stored settings, although it removes scheduled WM Guard cron jobs.