It means essential for the usage of the website, as in technically essential, like login or shopping cart.
The law doesn't say anything about it, though: this is just the interpretation and how courts have been treating it, so I wouldn't try to find loopholes around the word "essential" if you intent to follow it.
A court has ruled that tracking cookies used by ad networks, analytics and retargeting require consent [1].
Nothing stopping you from analysing your logged-user data, though (as long as you disclose it to your customers and comply with the rest of GDPR), so it's possible to have those kinds of measurements even without those stupid cookie banners.
The law doesn't say anything about it, though: this is just the interpretation and how courts have been treating it, so I wouldn't try to find loopholes around the word "essential" if you intent to follow it.
A court has ruled that tracking cookies used by ad networks, analytics and retargeting require consent [1].
Nothing stopping you from analysing your logged-user data, though (as long as you disclose it to your customers and comply with the rest of GDPR), so it's possible to have those kinds of measurements even without those stupid cookie banners.
[1] https://techcrunch.com/2019/10/01/europes-top-court-says-act...