These frame parameters enable or disable various parts of the frame, or control their sizes.
nilfor no scroll bars.
nilmeaning to use the default width.
nilstands for the standard fringe width, which is the width needed to display the fringe bitmaps.
The combined fringe widths must add up to an integral number of
columns, so the actual default fringe widths for the frame may be
larger than the specified values. The extra width needed to reach an
acceptable total is distributed evenly between the left and right
fringe. However, you can force one fringe or the other to a precise
width by specifying that width as a negative integer. If both widths are
negative, only the left fringe gets the specified width.
nilmeans don't display a menu bar. See Menu Bar. (The X toolkit and GTK allow at most one menu bar line; they treat larger values as 1.)
nilmeans don't display a tool bar. (GTK and Nextstep allow at most one tool bar line; they treat larger values as 1.)