Ask HN: How Do Karma Points Work?

Friends: I've been using HN for a number of years, and love it. But I'm perplexed by the karma system - specifically how points are added to a profile. For instance, earlier this week I posted an article. I began with 411 Karma points and by the next day, I had 415. The article I submitted recorded 8 points with 9 comments. I used to think it was a 1:1 ratio for points (minus the point I get for submitting). I imagine there may have been a downvote or 2, but then I would expect the 8 points to be "net." Or perhaps downvotes have an outsized effect on Karma vs. an upvote. Does getting comments on articles affect the karma count? Further, I've also noticed articles with more points in less time ranked below articles with less points in more time for front page rankings. I'm interested to understand this dynamic. I understand there are lots of behind the scenes (proprietary) algorithms to prevent gaming the system, and that certain levels of karma achieved enable outsized influence. But a general overview that doesnt give away the secret sauce would be useful - you know, for Science.