Selenium WebDriver is a popular tool used for automating web applications’ testing across different browsers. It allows developers and testers to interact with web elements and perform various actions, such as clicking buttons, filling out forms, and navigating between pages. Here are some common use cases of Selenium WebDriver:

1. Web Testing Automation: Selenium WebDriver is primarily used for automating web application testing. Testers can write scripts in various programming languages like Java, Python, C#, etc., to perform functional and regression testing of web applications.

2. Cross-Browser Testing: As Selenium supports multiple browsers like Chrome, Firefox, Safari, Internet Explorer, etc., it enables testing web applications across different browsers to ensure compatibility and consistency.

3. Filling Forms and Submitting Data: Selenium WebDriver can fill out forms on web pages and simulate user interactions, such as clicking buttons or submitting data.

4. Extracting Data: Selenium can extract data from web pages, which is useful for web scraping or gathering information for analysis.

5. Performance Testing: By automating repetitive tasks and interactions with web elements, Selenium WebDriver can be used for performance testing, measuring response times and evaluating application performance under different conditions.

6. Integration Testing: Selenium can be integrated into the development process to perform integration testing, verifying that different components of the application work together as expected.

7. UI Testing: Selenium WebDriver can validate the user interface (UI) of web applications, ensuring that the visual elements and layout are consistent and error-free.

8. Capturing Screenshots: Selenium can capture screenshots of web pages during the testing process, helping to document test results and identify visual issues.

9. Handling Pop-ups and Alerts: Selenium WebDriver can handle different types of pop-ups and alerts that appear during interactions with web applications.

10. Headless Testing: Selenium can be used in headless mode, where the browser runs without a visible user interface, allowing faster test execution and resource optimization.

To use Selenium WebDriver effectively, you need to choose a programming language (like Java, Python, C#, etc.), set up the WebDriver for the desired browser, and write test scripts to perform the required actions and validations. Keep in mind that while Selenium is a powerful testing tool, it is essential to use it responsibly and respect the terms of service of the websites you are testing.