New money
Starting tomorrow, you will start to see a new 500-baht banknote in Thailand.
The Central Bank says they will start circulating it on Monday.
The new banknote will have the same size and colour as the old one, but it will be much more difficult to forge or counterfeit (to illegally copy).
Can you still use the old banknote? Yes, you can, but the Central Bank expects the new banknote to completely replace it in about two years.
Maybe you should save one.