This section describes fundamental concepts for understanding screen
messages.
Screen message, screen description, descriptor
A screen message contains a record of the text and fields
of a particular application screen and also contains one or more screen descriptions
of that same application screen.
Default screen description
Whenever you create a new screen message, Enterprise Service Tools
automatically creates a default screen description inside the new screen message.
Screen recognition Screen recognition is the process by which the host editor
identifies among the available screen descriptions a screen description that
matches the currently displayed application screen.