The history of card payments is pretty rich.
Individual shops like electronics, but before that department stores, etc offered charge cards (or charge coins) since the 1870's. Charge cards/accounts are distinct from credit cards because you settle the balance at the end of the period (month) and it's not revolving debt with an interest rate. Its more like Net 30 terms.
Diners Club card was introduced in 1950 as a multipurpose charge card, usable at a large selection of merchants.
Eventually banks got in the game in the 50's and 60's and that enabled true credit cards, which were like a charge card but you could carry revolving debt on them
The finance side of it is equally rich. Merchants did/do offer their own financing, with mixed results. Car dealerships did well, and eventually made so much money they spun off entities like GMAC (the GM financing arm), which now operates as a bank - Ally - because of regulatory requirements on deposits etc