You can go to a store and they will give you credit to buy something that costs X paying X/12 a month. They give you something like a boleto for each month and you take your good home. If you don't pay your boletos your credit is ruined, you'll only be able to do that once, no other store will give you credit because they always check with credit institutions like SERASA.
Oh, and its a baaaaad idea to miss your payments, they charge ridiculous amounts for any day you miss. Your total due can double easily.
Boletos come in the mail so you can pay most of your bills here, we call those boletos too. Utilities, cable, internet, credit card, any kind of insurance etc. They all can send you boletos to pay online or at your bank.
Its common for old people to take a bunch of them to the bank on payday and ask the teller to pay them all. Me? I do it all online. My phone can scan the barcode with its camera, so its really easy to pay the bills.
Boleto is a thing in Brazil because a lot of people get paid in cash. A lot of people don't have bank accounts or credit cards. "Informal workers" are still a big part of the working force in Brazil even in this days.