Damerau–Levenshtein distance

The Damerau–Levenshtein distance is a way of measuring how different two words or phrases are from each other. It looks at each letter in each word or phrase and figures out how many changes would have to happen to turn one word or phrase into the other one. For example, if the word "cat" had to be changed to the word "dog," three changes would have to happen: the "c" would have to become a "d," the "a" would have to become an "o," and the "t" would have to become a "g." The Damerau–Levenshtein distance looks at how many changes like this need to happen in order to turn one word or phrase into another.