PostgreSQL's Fuzzy String Matching in YugabyteDB is a process that enables users to quickly filter down large datasets by matching strings with approximate criteria. This technique has various real-life use-cases including spell-checking, DNA analysis and detection, and spam detection. To achieve this, PostgreSQL extensions such as fuzzystrmatch are used, which support algorithms like Soundex, Metaphone, and Levenshtein for fuzzy string matching. These algorithms convert strings to their phonetic representations or calculate the minimum number of single-character changes required to transform one word into another. YugabyteDB supports these extensions and provides a straightforward way to use them without modifications, making it an ideal choice for applications requiring fuzzy string matching capabilities.