Unzer is a payment service provider from Germany that covers a broad set of payment methods. Alongside online checkout it handles payments at the terminal in physical shops, pay by link, and payment in instalments, so one contract can cover several ways of taking money.
Being German, Unzer is a European alternative to the American payment processors for merchants who want their payment partner under EU rules. The combination of online and in person payment makes it a fit for retailers that sell through more than one channel.