Levenshtein distance is an edit-distance metric that measures the minimum number of single-character insertions, deletions, or substitutions needed to transform one string into another. It is widely used in spelling correction, fuzzy matching, record linkage, and other tasks where approximate textual similarity is needed.
An edit distance metric that calculates the fewest delete, insert, and substitute operations required to change one word to another. For example, the Levenshtein distance between the words "heart" and "darts" is three because the following three edits are the fewest changes to turn one word into the other: 1. heart deart (substitute "h" with "d") 2. deart dart (delete "e") 3. dart darts (insert "s") Note that the preceding sequence isn't the only path of three edits.