These enable you to navigate the website and use its basic functions, such as remembering your cookie preferences, keeping you logged in, or retaining the contents of your shopping basket. They do not require your consent.
They remember the options you choose, such as language or region, so that they can display the website with those settings on your subsequent visits.
They measure the number of visits and how the website is used (page views, time spent on the site and the source of the visit) in order to compile statistics.
They create a profile based on your browsing habits to show you adverts related to your preferences on this and other websites, and they measure the effectiveness of the adverts.