Can you give an example of a negative test case?

A negative test case checks that the system correctly handles incorrect or unexpected data.

Example of a negative test case for a login form:

• Enter an incorrect password for an existing user.
• Expected result: the system should display an error message "Incorrect password" and prevent login.

Another example:

• Submit an empty value in a required form field.
• Expected result: a message about the field being mandatory appears.

Such tests help ensure that the application is resilient to errors and does not break when incorrect input is provided.