We're back to whatever forms of trade you can source locally in that case, but that should not surprise anyone who observes regions that are actually in crisis, because that is how the economy functions in those regions. You do your best to do something nice for your neighbors and they do their best to do something nice for you, and anything that requires global trade or supply lines simply doesn't happen.
Having a copy of your own medical records could be critically important if suddenly your friend who is a doctor is now your doctor because there's nobody else.
Money tends to be worthless is such situations anyway - it's backed by the full faith and credit of a government that best case no longer cares about you and worst case no longer exists. So you aren't going to worry about your bank account, nobody will accept credit or debit anyway.
There is a whole lot of other data on the Internet that can be very, very useful in such situations. Even just having a few hundred hours of collected kids TV shows means you can sit them down in front of Bluey while the adults do stuff that is critical for survival. Knowing how to build a smelter and bellows out of clay that you can find locally means you can restart metal production in a matter of days rather than thousands of years. Knowing what the local plant species are and which are edible might keep you from starving. Knowing how to scavenge parts and wiring, as well as what their datasheets are and how you need to hook them up, means you can fix broken electronics and potentially create new ones, which gives you continuing access to knowledge.
Having a copy of your own medical records could be critically important if suddenly your friend who is a doctor is now your doctor because there's nobody else.
Money tends to be worthless is such situations anyway - it's backed by the full faith and credit of a government that best case no longer cares about you and worst case no longer exists. So you aren't going to worry about your bank account, nobody will accept credit or debit anyway.
There is a whole lot of other data on the Internet that can be very, very useful in such situations. Even just having a few hundred hours of collected kids TV shows means you can sit them down in front of Bluey while the adults do stuff that is critical for survival. Knowing how to build a smelter and bellows out of clay that you can find locally means you can restart metal production in a matter of days rather than thousands of years. Knowing what the local plant species are and which are edible might keep you from starving. Knowing how to scavenge parts and wiring, as well as what their datasheets are and how you need to hook them up, means you can fix broken electronics and potentially create new ones, which gives you continuing access to knowledge.