@RoronoaZoro Well, there are basically 2 aspects. Technically not being able to send/receive money (exclusion from SWIFT) and prohibiting other countries from accepting the money in order to buy something with it. This means that the rouble can only be spent in your own country and is then worth as much as my toilet paper.
@Zaba19 Yes, I already had Swift on my screen before, but I was briefly confused as to what was meant by sending us back to the Stone Age :) But that's how you turn off the tap for those who don't care whether Russia is in Swift or not :)