A cookie on the internet is a small piece of data that a website stores on a users browser. It consists of a small text file with a unique ID which is an anonymous number randomly generated. There are two copies of it, one is stored on the users device and one is stored on the website. Cookies are used to identify users, manage their browsing sessions, facilitate personalized user experiences, ad targeting, and much more. They are used to store information such as shopping cart contents, registration or login credentials, and user preferences. Cookies can also be used to save for subsequent use information that the user previously entered into form fields, such as names, addresses, passwords, and payment card numbers. Cookies are essential to the modern internet experience and help web developers give users a more personal and convenient website visit. However, some cookies can be used to track users without their consent by cybercriminals, making them a serious vulnerability to privacy.