Geo Targeted Caching is a plugin for WP Super Cache that makes it so that each page is cached on a per country basis. This can be useful if pages on your website contain content that differs based on the location of a visitor.
The plugin requires that your web server has GeoIP functionality available or the PHP GeoIP extension is installed.
For an explanation of why caching can be problematic with dynamic content, and how Geo targeted page caching / cache page key modification (used by this plugin) compares to other methods, please see this page: Differences between caching methods with Geo targeted content.
To use the plugin, first extract the contents of the zip file into your Super Cache Plugins folder. You should not be using the Super Cache Plugins folder in its default location, see here for how to change it: Moving the WP Super Cache Plugins folder.
In your WordPress admin panel, go to the WP Super Cache settings page. Go to the advanced tab. Under the Caching section, choose Use PHP to serve cache files.
Save the settings and go to the Plugins tab of the WP Super Cache Settings. Scroll down to find the entry Geo Targeted Caching. Check the enabled option then press the update button.
After doing this, you may want to clear the cache to remove all old copies of cached files that have been cached on a worldwide basis rather than per country. This is not necessary, but just removes the old cached files no longer needed.