The video tutorial explains web cookies, small text files stored by web servers on browsers to remember user preferences and activities. It uses Kayak.com as an example to illustrate how cookies work, storing user settings like language and currency. The tutorial covers different types of cookies, such as session and persistent cookies, and discusses their roles in enhancing user experience. It also addresses security concerns, highlighting how cookies can be exploited by hackers. Finally, it demonstrates how to view and manage cookies in a browser, emphasizing the importance of periodically clearing them for security.

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