Cookies are small text files that websites store on your computer or device when you visit them. They help the website remember your preferences, like your login information or items in your shopping cart. This makes your browsing experience smoother and more personalized, as the site can recall your past interactions. There are different types of cookies, such as session cookies, which are temporary and deleted when you close your browser, and persistent cookies, which remain on your device for a set period. While cookies can enhance your online experience, it's important to manage them for privacy and security reasons.