Nicolas Appert was a man who lived a long time ago and he loved food. He wanted to figure out a way to keep food fresh for a really long time, so that people could have yummy food even when it wasn't the season for it.
So, Nicolas came up with a clever idea. He put food in jars and then he heated them up and sealed them really tightly. This helped to keep the food safe and fresh for a long time. He also put the jars in cool places to stop any bacteria from growing on the food.
People really liked Appert's idea and soon he became famous for inventing a way to preserve food. This was really important back then because people didn't have refrigerators or freezers to keep their food fresh.
Nowadays we have lots of ways to preserve food, but we still remember Nicolas Appert for coming up with the first idea of putting food in jars and sealing them tight to keep them safe and yummy for a long time.