lodash is a widely-used JavaScript utility library providing a consistent API for manipulating arrays, objects, strings, numbers, and functions. It offers a monolithic UMD build, per-method modular packages, and a functional programming variant (lodash/fp) with auto-curried iteratee-first data-last methods. The library is feature-complete and actively maintained, though its build tooling ([email protected], [email protected], jscs) is outdated and targets ES5. It is not an application but a reusable library, with entry points in lodash.js and lodash/fp. The codebase demonstrates clean abstractions and extensive internal reuse, but internal modules like the FP conversion engine are tightly coupled.