> Is called cash :) It's accepted everywhere.

Surprisingly, it’s not!

A non-Swedish friend studying in Sweden recently told me of a situation (I forget the exact details) where she could not pay with cash. They only accepted payment via Swish[^1] (mobile payment system).

At the time she was with a Swedish friend which was the one to pay for both of them, with my friend paying her friend in cash.

[^1]: https://www.theguardian.com/business/2016/jun/04/sweden-cash...