Hi @Boban J., yes exactly based on cookies.
We drop a persistent cookie to track new vs returning. If we are just now creating the persistent cookie then we know they are new, if we are reading already the persistent cookie and have seen it in Dynatrace, Dynatrace knows this is a returning user.
Bit more detail is available here: https://www.dynatrace.com/support/help/shortlink/c...
Hope it helps you out!
Yes, if the users clear their cookies and they're tagged, they will count as a new user. Also, cookies are only valid for 30 days. So even if the user doesn't clear their cookie, after 30 days they will be considered a new user (if they come back).