Okay kiddo, the Winter War was a battle that happened in Finland in 1939 and 1940. Finland was trying to protect its land from the Soviet Union, which was bigger and stronger.
Now, imagine you're playing a game and your opponent has many more players and better equipment than you do. Finland was in a similar situation.
Despite the odds, Finland fought hard against the Soviet Union during the Winter War. And guess what, some brave people in Finland won and protected their land!
Now, many movies, books, and TV shows have been made about this battle. They want to remind everyone of the bravery of the Finnish soldiers and their country's history. So, you might see this story in different forms of entertainment.
It's like telling a story to other people and reminding them of a great person you know. It teaches them that with hard work, bravery, and determination, they can also achieve great things. And that's why the Winter War story is so popular!