All modern browsers have tools to help you delete or block cookies from being set. But it’s important to remember that many sites need cookies to work properly, so by deleting or blocking them, some parts of these websites might not function correctly.
An example of what can be stored in a cookie is:
A name: The cookie’s name, which is unique to the site that set it.
Site name: The name of the domain or sub-domain that set the cookie.
Expiry date: After the expiry date, the cookie will be automatically deleted. Some cookies will expire when you close your browser. These are called session cookies.
Other cookies may expire weeks, months or years after being set. These are called persistent cookies.