Global bookmark service: you can collect and manage your personal ratings from any Web browser. Thus, you can find your previously rated pages using any computer.
Personal recommendations: the system can advise you Web pages that you may find interesting based on your and others' previous ratings.
Feedback on your work: you can add rating facilities to your own Web pages, and collect ratings from others.
There is only one requirement to use SELECT: your Web browser have to accept cookies from this server.
You may want to read the page on how to use this service easily from your browser.
There's also a guide on how to make your Web pages easy to rate.