Secure multi-party computation is like having a secret clubhouse with your friends where only you and your friends know the password to get in.
Let's say you and your friends want to plan a surprise party for another friend, but you want to keep it a secret from everyone else. You don't want anyone to find out about the party, especially not the friend you're throwing the party for.
To keep the party a secret, you and your friends decide to use secure multi-party computation. This is like having a secret code that only you and your friends know, and it allows you to communicate with each other without anyone else being able to see or hear what you're saying.
To use secure multi-party computation, you and your friends each have a secret key, like a password, that you keep to yourselves. You also have a special algorithm that allows you to combine your secret keys together in a certain way. When you combine your secret keys, you create a new key that can be used to encrypt messages that only you and your friends can read.
So when you want to plan the party, you use this new key to encrypt your messages to each other. This way, even if someone else intercepts your messages, they won't be able to see what you're saying because they don't have the secret key.
Secure multi-party computation is a way for you and your friends to work together on something important, like planning a surprise party, without anyone else finding out about it. So the next time you want to keep a secret from the rest of the world, remember your secret clubhouse and your secret code!