A cookie is a small text file that a website places on your device when you visit. It is stored in your browser and sent back to the website on future visits so the site can recognise your browser and remember certain information.
Cookies are not programs — they cannot run code, carry viruses, or access other files on your device. They are simply data files used to make websites work more reliably and to understand how visitors use them.
Some cookies are set directly by the website you visit (first-party cookies). Others are set by third-party services that the website uses, such as analytics tools or embedded content.