Challenge: Levenshtein distance for quiz-like web sites and alike

I found this great algorithm, which can be used for quiz-like inputs where you want to check if the person knows the answer but don't care about spelling or accidental errors without hard coding like .trim() method in js. It is pretty simple but yields great results. It can be used for plagiarism detection and what not.
Here is the [wikipedia page](https://en.wikipedia.org/wiki/Levenshtein_distance). I think it would be kinda fun to see this explained.