Cookie Banner
A cookie banner is the notice that informs website visitors about the cookies in use when they first arrive and asks for their consent before any cookies that are not strictly necessary may be set.
In practice
Only a banner offering a genuine choice is lawful: accepting and rejecting must be equally easy to reach, and no setting may be pre-selected as "accept all". Cookies that are strictly necessary on technical grounds, for a shopping basket for example, do not require consent at all.