The Alert element can be used for any kind of text information.
Settings:
Mark UI invalid: If checked the User cannot complete the UI if the Alert element is shown, used with Conditions. For example if you have an Assessment element with label: "Is the machine in order?" and 2 options "YES", "NO", you can place the Alert inside a "NO" condition. In this case the User will not be able to complete the UI until the answer to the Assessment "Is the machine in order?" is "YES"