This document discusses writing documentation for APIs and SDKs. It describes APIs and SDKs, typical documentation deliverables, ideal information to include, and reference information. It outlines benefits and drawbacks to technical writers in this specialty market. It provides suggestions for breaking into the market, including training, self-paced learning, sample projects, and resources. The document also discusses automation tools, help authoring tools, text editors, search/replace tools, and considerations for help formats and context-sensitive help.