What is the main difference between functional testing and visual testing?

The main distinction between functional testing and visual testing lies in their focus and objectives. Functional testing is primarily concerned with validating that an application performs its intended functions correctly. It checks whether specific features work as per the requirements and ensures that the application responds appropriately to user inputs and navigates as expected.

On the other hand, visual testing examines the design and presentation aspects of an application, assessing elements like layout, colors, fonts, and overall aesthetics to ensure they align with the intended design specifications. This type of testing is crucial for maintaining the visual consistency and user experience of the application across different devices and screen sizes.

In contrast, the other choices misrepresent the nature of either functional or visual testing. For example, the idea that functional testing is always automated or that it emphasizes server-side changes does not accurately reflect its broader focus on functionality, which encompasses both front-end and back-end aspects of applications. Similarly, the assertion that visual testing is solely manual and that functional testing requires user input are oversimplifications that do not capture the comprehensive aspects of both testing methods.