Reddit glossary
What is Karma on Reddit?
Karma is the score on your Reddit profile that roughly shows how much other people liked your posts and comments.
Your karma goes up when people upvote what you share and goes down when they downvote it. Reddit splits it into post karma and comment karma, and the total shows on your profile.
It is not money and it does not unlock anything by itself. But some communities use it as a filter, for example by asking for a minimum amount before you can post.
If you are promoting something
Do not chase karma for its own sake. Karma is a side effect of being useful. If you help people in a community for a few weeks, it takes care of itself.