WebdriverIO is a popular JavaScript framework based on Node.js for end-to-end automation testing, which simplifies browser interaction through various commands. This tutorial provides detailed instructions on how to use WebDriverIO browser commands to perform actions such as opening and closing browser windows, navigating pages, handling window sizes, and managing cookies. It contrasts WebDriverIO's setup with traditional Selenium by highlighting the direct usage of globally initialized 'driver' or 'browser' objects, eliminating the need to create separate objects. Key browser commands include opening new windows with `newWindow`, switching between windows with `switchWindow`, and manipulating window size using `setWindowSize`. Additionally, it covers navigation commands like `navigateTo`, `back`, and `forward`, and page management commands such as `pause`, `refresh`, and timeout settings. The tutorial emphasizes efficient test automation and suggests using a Selenium Grid for scaling, with examples provided to illustrate command usage.