A cookie is a small text file that is saved by the websites that you visit on your computer.
A cookie can contain information, such as a user ID or preferences, which the websites use to personalize content, track the pages you've visited or to save your password so you do not have to re-enter it each time you visit our websites.
A cookie can be classified by its lifespan and the domain to which it belongs. By lifespan, a cookie is either a:
• session cookie – which is erased when the user closes the browser
• persistent cookie - which remains on the user's computer/device for a pre-defined period of time
As for the domain to which it belongs, there are either:
• first-party cookies - which are set by the web server of the visited page and share the same domain
Enabling these cookies is not strictly necessary for the websites to work but it will provide you with a better browsing experience.