Retrofuturism is when people imagine what the future would have looked like in the past. So, it's like imagining what people in the past thought the future would be like when they were alive.
For example, people in the 1950s thought that by the year 2000, everyone would live in flying houses and there would be robots who would do everything for us. Of course, that didn't happen, but it's fun to imagine what the future could have been like if things had turned out differently.
Retrofuturism isn't just about imagining the future from the past - it's also about mixing old and new designs. For example, you might see a car that looks like it's from the 1920s, but it has high-tech features that you would find on a modern car.
So, retrofuturism is a mix of old and new ideas. It's kind of like taking a trip back in time and then imagining what the future would have looked like from that perspective.