You can set line thickness (width) either in the measurement unit
selected under Set unit of measurement
in the Page module, or
you can select one of the pre-set widths. Selection is simple: Click
on the number field, use the [Esc] key to clear the line, enter the
desired value and then press [Return] to make sure that the new value
will be adopted. With this function you can create lines that are over
a metre wide, but in that case you are unlikely to see much of your
document!
To select one of the eight pre-set line thicknesses, click on the
desired icon, which will then be framed. The value in the number field
will show the actual thickness of the line in the chosen unit of
measure. The dotted line shown on the far left is called a
Hairline
. Hairlines are always one pixel wide in the
resolution of the output device and so do not change in width if
you magnify their frame on screen. If you print a hairline on an
imagesetter, it would be only 1/100 mm (1/2540 of an inch) thick in
the highest resolution, and would be difficult or impossible to see
after copying.