This document discusses an introduction to acceptance test-driven development (ATDD) using Cucumber and RSpec. It explains that ATDD involves collaborating with stakeholders to write automated acceptance tests before development begins. The tests describe features and scenarios in a way that stakeholders can understand. Cucumber uses a plain language format to define tests and map them to code via step definitions. RSpec is also used for unit testing. The document provides examples of Cucumber feature files and touches on integrating Cucumber with RSpec during the development process.