Data-driven testing is a methodology where test input and output values are read from external data sources like files or databases. A single test script can be used to execute multiple test cases by varying the test data. Maveryx is a tool that supports data-driven testing through features like intelligent object recognition, separation of test logic from data, and reading test data from sources like Excel. The document provides an overview of data-driven testing and examples of how to create a data-driven test script using Maveryx.