A library is a collection of reusable code that provides specific functionality for applications. Instead of reimplementing common tasks, developers import libraries to speed up development. Libraries encapsulate logic for tasks such as data formatting, network requests, UI components, or cryptography. They help maintain consistency, reduce duplication, and improve reliability. Many programming ecosystems include thousands of libraries published by the community. Using libraries allows developers to focus on core business logic rather than low level details.
how it works
Libraries are installed through package managers such as npm or language specific tools. Projects reference library functions in their code, and the compiler or runtime loads them at execution. Libraries may depend on other libraries, forming dependency graphs. Versioning helps ensure compatibility between library updates and existing applications. Good libraries include documentation, tests, and stable APIs. Overuse of libraries can lead to bloat, so teams must choose dependencies carefully.