Okay kiddo, the Yeomen of the Guard is a group of very important people in England who are responsible for taking care of the king or queen. They wear special fancy clothes that look like they're from a long time ago and they carry big pointy sticks called halberds.
They're called Yeomen because a long time ago, they were actual soldiers who fought in battles to protect the king or queen. But now, they don't have to fight anymore, they just walk around and look cool.
The reason they're called the "Guard" is because they guard the king or queen. That means they make sure no bad guys sneak up and try to hurt the king or queen. They also make sure that no one gets too close to the king or queen without permission.
The Yeomen of the Guard is a very special group because they've been around for a really long time, since the 1400s! That's almost 600 years! They still do their job today and they're very good at it.