jsdiff is a JavaScript library that provides text differencing capabilities, allowing developers to compare strings and identify differences at the character, word, or line level. It supports various diffing methods, including diffChars, diffWords, and diffLines, and can generate unified patches for version control workflows. The library is based on the Myers diff algorithm and is available under the BSD-3-Clause license. An online demo is available at incaseofstairs.com/jsdiff, enabling users to experiment with different diffing strategies in real-time.