Okay kiddo, so imagine you have two puzzle pieces. One puzzle piece is a circle and the other puzzle piece is a triangle.
Now, you want to put them together to make a bigger picture, but they don't fit perfectly because they are different shapes.
But what if you could make the circle puzzle piece a little bit bigger or smaller, and make the triangle puzzle piece a little bit bigger or smaller, so that they match up better?
That's kind of like what elastic matching does. It helps to match up things that are a little bit different, by making small changes to make them fit together better.
For example, in some computer programs, elastic matching can be used to match up two images. The program might stretch or shrink the images a little bit, or twist them a little bit, to make them match up better.
So, elastic matching is kind of like puzzle magic, making pieces that don't quite fit together to fit together better with a little bit of stretching or shrinking.