Okay kiddo, imagine you have a big list of words like "cat", "dog", and "bird". Now, imagine another list with the same words but written differently, like "kat", "dogg", and "byrd".
A concordance system is like a superhero that helps you match up these different versions of the same word. It looks at all the words in a big book (called a corpus) and organizes them so that you can easily find all the different forms of a word, like "run", "running", and "ran".
This superhero also helps you find where these words appear in the book so that you can see how they are used in different sentences. This can be really helpful if you're trying to study a language or understand how a word is used in different contexts.
So, basically, a concordance system is like a super helpful friend who helps you match up different versions of a word and find where they appear in a big book. Cool, huh?