How It's Used - IBM 3270 Operator's Manual

In all applications for the selector pen, a list or a table is
displayed, and the operator selects items from it with the
selector pen. Although all applications are basically similar, a
user's specific application could be unique. Your supervisor will
explain your organization's application(s) and the way you are to
use your selector pen.
The first character of each selectable field on your screen is
called the designator character. There are only two possible
designator characters and, by remembering them, you can
identify the fields that you can select. The designator character
will be either a question mark (?) or a greater-than sign (>).
Figure 42. Designator characters tell you much about the data on your
screen.
Extras for the 3270
103
How It's Used
I