We need to make a small site for voting any questions. The user enters the site, first sees the most popular votes for beginners, votes actively participates in polls. After that, to be able to leave comments and vote polls with a higher rating, you will have to register.
Use cookies for the guest, write points there and after registration add these points to the rating. And if the user sees the cookie and changes the value to its own, then after registration these values will be sent to the server, etc. Or store everything in the database or in XML files on the server? Then I am afraid that from requests of the guest the server can fall or still that. In short, a complete mess in my head.