Visual regression testing is a crucial aspect of software testing that focuses on verifying the visual appearance of web applications across different states and environments. Unlike traditional functional testing, which primarily checks the functionality of features, visual regression testing specifically examines whether changes in the codebase have introduced unintended alterations to the user interface.

This testing methodology involves capturing screenshots or snapshots of web pages during various stages of development or after updates. These snapshots serve as baseline references for subsequent tests. When changes are made to the application, automated tools compare the new screenshots with the baseline images to detect any discrepancies in layout, styling, or content rendering.

Visual regression testing ensures the visual integrity of web applications by identifying visual defects such as layout shifts, font changes, color variations, or missing elements. By detecting these issues early in the development process, teams can prevent visual regressions from impacting the user experience and maintain consistency across different browsers and devices.

Overall, visual regression testing plays a vital role in ensuring that web applications deliver a visually appealing and consistent experience to users, ultimately enhancing usability and satisfaction.