It's a very silly question, but how do I vote? I've noticed that posts have score, and I assume it's calculated by user votes, but I haven't found the UI element to cast my vote. I am of course logged in.
Also, how do I mark a post/comment as "insightful", "humoristic" etc. ?
Slashdot has adopted the interesting system of giving logged in users randomly a number of 'moderation points', which can be used to moderate posts as you describe. You can increase the chances of getting these points by being logged in and browsing comments and by having been a member for a certain length of time, but it is largely a matter of chance.
There is a (very) old write up here that is quite in-depth on the how and why. Some of the details may be a little different now but the mechanics are largely the same. The FAQ topic covers it in less detail.Tweet