The document discusses building chatbots using Google Cloud Functions and API.AI. It covers the design, development and deployment process. For design, it discusses creating a persona, style guide and sample dialogs. For development, it explains how conversations work with speech to text, natural language processing and text to speech. Cloud Functions is presented as a serverless platform to build event-based microservices for chatbots. API.AI is demonstrated for natural language understanding. Integrations with Actions on Google and other platforms are also covered. The document concludes with resources for conversational design guidelines.