Ordinarily, sites will show up in your browsing history and can be seen whenever uses your Kindle. With Private Browsing, you can surf the web without saving a record of your visits. Pages you view during a Private Browsing session do not remain in your browser’s history, cookie store, or search history after the session is over. Note: this will not hide your browsing history from your isp or the websites you visit.
To enable Private Browsing, tap the page action icon at the bottom of the screen and select Enter Private Browsing. While Private Browsing is enabled, tabs appear in purple and have the word Private after the website name. To disable Private Browsing, tap the page action icon and select Exit Private Browsing. You might then be prompted about whether you would like to keep or delete any downloaded content.
I will sometimes to use this feature if I need to borrow someone’s Kindle to look something up on the web.