What's up with the $20 bill being sought after by counterfeiters the most when its face value is shit in comparison to $100? Stores being scammed with fake cash that a pen is needed to distinguish between genuine and fake, its a problem they encounter quite a lot. US Dollars are printed with a single layer consisting of linen and cotton, which is easy for counterfeiters to exploit (like bleaching a $5 bill imprinting $100).

That's something you don't hear about as much with Swiss Francs as they have top notch security features (they're printed vertically at different sizes). Every denomination (from 10-1000) features a globe with security ink showing dynamic color changes and a shifting arc when tilted. The bills are printed using an innovative three-layer composite material known as Durasafe which involves 8 complex printing processes.