Definition:
Private browsing, also known as private mode or incognito mode, is a web browser feature that limits the information from a session retained on the device. It allows users to visit pages without adding them to the browser’s regular history and deletes certain temporary data when the private session ends.
Its main purpose is to reduce the traces available to other people who use the same browser. It does not in itself hide activity from the websites visited or make the connection anonymous.
Table of contents
Private browsing vs. anonymous browsing
Private browsing and anonymity protect different aspects. To understand their limitations, it is useful to distinguish these situations:
- IP address: private mode does not in itself change or hide the IP address from which the connection is established. Websites can receive it and use it alongside other data to recognise activity.
- Identification on services: if someone signs in to an account, the service can associate their activity with that account even when they use a private window.
- Visibility outside the device: the internet provider or a network administrator can observe certain information about connections. What they can see depends on encryption and network configuration, not just the browser mode.
- Files and bookmarks: downloads and bookmarks created during the session can remain after private windows are closed.
- Extensions and external programs: extensions authorised to run in private mode can access information according to their permissions. This mode also does not prevent malicious software installed on the device from recording activity.
Tor Browser uses a network of relays to make it harder to link the origin of a connection with its destination. It is not simply a private window, nor is it limited to accessing the dark web. It does not guarantee anonymity in every situation either: signing in to an account still reveals that identity to the service.
How to browse in private mode
Browsers that include this feature allow users to open a private window or tab from their menu. The name and steps depend on the browser and device. In Chrome, for example, the option is called "New Incognito Window".
A private session maintains its own temporary data. Cookies can be used while it is open to support features such as signing in or maintaining a shopping cart. This mode therefore does not automatically disable all cookies; restrictions on third-party cookies depend on the browser and its settings.
To end the session, all corresponding private windows or tabs must be closed. Closing just one is not always enough. When the session ends, the browser deletes the temporary data it manages for that session, but it does not delete downloads or records retained by external services.
Features of private browsing
This feature can be useful for separating a session from regular browsing. Its characteristics include the following:
- Limited local history: pages visited are not added to the browser’s regular history. This does not mean that other records on the device or network disappear.
- Separate sessions: it allows a service to be used without automatically relying on cookies from the normal session. It can also facilitate temporary access to another account.
- Less form data retained: data entered during the session is generally not saved for later reuse in the browser. The website to which it is submitted may retain it.
- Use on shared devices: it helps avoid leaving a browser session signed in after all private windows are closed. It does not turn someone else’s device into a trusted environment.
Private browsing does not guarantee identical search results for all users. Although it separates the session from some previous activity, search engines can still consider approximate location, language, device and query context. It therefore does not provide a neutral and definitive measurement of a page’s search ranking.