API documentation is essential for a successful API, encompassing various components to cater to diverse user needs. These components include recipes and examples, which offer use-case-focused tutorials with code snippets that users can easily copy and tweak; topical guides that delve into advanced concepts and design philosophies, helping users understand the broader context and best practices; and reference guides, which provide detailed descriptions of endpoints, parameters, and expected responses, serving as a critical resource despite being the least engaging part of the documentation. Additionally, support forums offer a platform for addressing unstructured and unique edge cases, while marketing pages play a crucial role in persuading potential users to invest in the API by presenting a polished and appealing front. Effective documentation not only includes traditional text but also incorporates error messages with documentation links, change logs, SDKs, and integrations to streamline the user experience and facilitate seamless API usage.