When navigating the internet, browsers typically maintain a previous history of the websites the user has visited. This history usually contains the pages’ URLs and the website’s cookies.
These history files remain inside the browser to be accessed later, under specific conditions, by both the visitor and the visited websites.
Can websites see your browsing history?
Websites are generally unable to see the browsing history of other websites. A website is technically allowed to only access the visited pages of this particular website. Nevertheless, third-party content providers like ads might still be able to track your browsing history.
Can Websites See Your Built-in Browser History?
Almost all browsers have a built-in feature that stores web pages’ URLs the user visited while using this particular browser. Users can usually view their browsing history by pressing CTRL + H or via the browser’s navigation menus.
This built-in history panel is part of the browser itself and can be read by only users who have access to the browser. Unless there was a vulnerability in the browser or its add-ons, websites have no access to the browser’s local data and history.
The Important Role of Website Cookies
Cookies are pieces of textual information a website stores in the user’s browser when visiting it. Primarily, websites rely on cookies to save information about the users’ authentication status and their preferences (language, currency, theme, font size, …).
Cookies are the key technique for the "remember me" option. When a user logins to a website, this website creates a cookie on the user’s browser. This cookie helps the website remember the authenticated users the next time they visit it so it doesn’t ask them again for their credentials.
Technically speaking, cookies are created and managed independently for each domain. That said, websites are only allowed to access their own cookies on the user’s browser. So website A can NOT access cookies created by website B even if they are visited on the same browser, and visa versa.
Using Third-Party Cookies for Tracking Browsing History
When visiting a website, some of its content might be provided from other domains that can be different than the visited website. This is particularly the case with online advertisements, which are typically served by various ad providers.
When visiting a website with third-party content like ads, you are allowing the content provider websites to create and store their own set of cookies on your browser.
This means when visiting a website A that, for example, shows google ads, multiple sets of cookies are created. One for website A itself, and other third-party cookies for each of the displayed ad providers the website A hosts. Both created (primary and third-party) cookies may contain information about the webpage being displayed and its content.
So when you afterward visit website B which also shows google ads, ad providers will be able to detect their own cookies previously created on the same browser. Accordingly, they will be able to know your preferences from the pages you visited earlier on website A (and other visited websites that host their ads).
Ad providers usually use their cookies to track the user’s preferences for a better ad experience. However, there is no guarantee all third-party content providers are totally legitimate and trustworthy.
Does Disabling Cookies Prevent Online Tracking?
Most browsers do provide options to disable cookies, they also allow their users to manage and delete any stored cookies by domain names. Additionally, users can use the private mode of their browser so all cookies are automatically deleted upon closing the browser window.
Although this practice would prevent any third-party content provider from tracking your online activities, it might break some essential functionalities of the visited website.