1. Installation: Capybara is primarily used with Ruby on Rails applications and requires additional setup compared to pytest, which is a testing framework for Python that can be easily installed using package managers like pip.
2. Syntax: Capybara uses a DSL that closely mimics user interactions on a web browser, making it highly readable for writing functional tests, while pytest follows standard Python syntax and is more versatile for a wide range of testing scenarios.
3. Focus: Capybara is specifically designed for acceptance testing and UI testing, providing high-level abstractions to interact with web pages, whereas pytest is a general-purpose testing tool that can be used for unit testing, integration testing, and more.
4. Selectors: Capybara provides a range of powerful selector methods for locating and interacting with elements on a web page, making it easy to write expressive tests, whereas pytest relies on libraries like Selenium for similar functionality.
5. Browser Compatibility: Capybara supports multiple drivers to interact with different browsers, making cross-browser testing easier, whereas pytest requires additional libraries or plugins to achieve similar browser compatibility.
6. Community Support: Capybara has a strong community within the Ruby on Rails ecosystem, providing extensive documentation and resources, while pytest has a large community in the Python development world with a wealth of plugins and integrations.

In Summary, Capybara and pytest have key differences in terms of installation, syntax, focus, selectors, browser compatibility, and community support, catering to different testing needs in web development.