SDK (Software Development Kit)

An SDK (Software Development Kit) is a packaged collection of tools — libraries, code samples, documentation, and sometimes debugging utilities — that makes it easier for developers to build applications for a specific platform or to integrate a service.

Where an API defines the interface, an SDK wraps that interface in ready-to-use code for a particular language or environment, handling boilerplate like authentication and error handling. A good SDK dramatically lowers the effort to adopt a platform, which is why developer-facing companies invest heavily in them.

For PMs working on platforms, developer tools, or integrations, the SDK is a key part of the developer experience (DX). Its quality — clear docs, sensible defaults, broad language support — directly affects adoption, much like UX affects adoption for end-user products.