First-party cookies are small pieces of data stored on a user's device by the website they are visiting. These cookies help the website remember information about the user, such as login details, preferences, and items in a shopping cart. This enhances the user experience by making the site more personalized and easier to navigate. Unlike third-party cookies, which are set by external domains, first-party cookies are created and accessed only by the website the user is currently on. This means they are generally considered more secure and privacy-friendly, as they do not track users across different sites.