A DoubleField is a component that allows the editing of a double (floating-point number),
and allows the user to avoid messy conversions to and from strings.
An IntegerField is a component that allows the editing of an integer (whole number),
and allows the user to avoid messy conversions to and from strings.
Used with non-GUI applications to prevents a "fly-by"
disappearance of the terminal window
in some environments by pausing execution until the user
presses the Enter key.