Green shield stamps were little stickers that were given out to customers as a reward when they bought things. Kind of like when you get a sticker for doing a good job at school!
The idea was that if you collected enough green shield stamps, you could exchange them for cool things like toys, kitchen gadgets, or even a bike!
Every time you bought something, you would get a certain number of stamps depending on how much money you spent. So if you spent a lot of money, you would get more stamps than if you only spent a little bit.
People would save up their stamps in a special book until they had enough to get something they really wanted. It was like a fun little game that made shopping more exciting!
Nowadays, we don't really use green shield stamps anymore because there are other ways to reward customers for buying things. But they were a really popular thing back in the day!