Creating Price Rules - PrestaShop tutorial
"Price rules" can take two forms:
Cart rules. These are actually the successors to vouchers, as they were known in previous versions of PrestaShop.
Basically, it enables you to create per-customer voucher codes, but also much more.
Catalog price rules. Enables you to assign price reductions by category, manufacturer, supplier, attribute or feature.
For instance, you can set a rule that would say that for Spanish customers belonging to the "Good clients" group would get 10% off on your Electronics category and all Sony products for the first week of July.