Private Browsing
In a Private Browsing session, the browser won't keep any browser history, search history, download history, web form history, cookies, or temporary internet files. However, files you download and bookmarks you make will be kept. Remember, using the Private Browsing does not prevent the Internet Service Provider nor your employer from tracking the site that you visit because when you request a web page, the request has to go through a server(s).
Opera
Currently, Opera browser does not have Private Browsing.
Currently, Opera browser does not have Private Browsing.