Data curation is like organizing and sorting your toys. When you have lots of different toys, it can be hard to find the one you want to play with. To make it easier, you organize them - like you put all your Duplo blocks together in one spot, your stuffed animals in another spot, and your Lego sets in a third spot.
Data curation is similar to this. When you have lots of different facts, figures, and ideas (like those toys), they can be hard to find and use. To make things easier, people organize that data into groups of similar things (like with the toys). This makes it easier to find the data when you need it.