The operator runs the casino site and handles your account, payments, and...

https://wiki-cable.win/index.php/What_Does_It_Mean_When_People_Say_a_Slot_Is_%E2%80%9CJust_Presentation%E2%80%9D%3F

The operator runs the casino site and handles your account, payments, and access to games. The slot provider makes each game. Its name in a catalogue helps you find other games from the same maker