Cookies have an expiry time. Cookies stored on your device will therefore automatically disappear. How long a cookie exists depends on how long the program needs to remember information. This should not be longer than necessary.
Some cookies exist for a short time, namely as long as your website visit lasts. For example, our chat program uses them to remember which questions you ask. Otherwise, it will lose them already when you click through to the next page. When you close your browser, you automatically delete these cookies.
Other cookies last longer than your website visit. It can be a day, but also a week, a month, a year or even longer. When you close your browser, these cookies remain on your device until they disappear by themselves. You can also delete them directly yourself via your browser settings.