Point Earning Rule
A Point Earning Rule (or Distribution rule) is a Point Rule that applies to your store that will determine how points are awarded/sent to customers. They govern how customers/users can earn points.
These distribution rules award points based on products. If you want a to give customers 10 points for purchase of any laptop product, you would use a catalog distribution rule.
These distribution rules award points based on a customer's shopping cart. If you want to give customers 10 points for any purchase with a subtotal over $400, then you would use a shopping cart distribution rule.
These distribution rules award points based on a customer's actions. Notice how these rules are not tied to a purchase like the other two. These rules are used to award points for things such as voting in a poll, signing up for a newsletter, and other customer actions. If you want to give customers 10 points for creating a new customer account, you would use a customer behavior rule