Though many windows may exist simultaneously, at any time one window
is designated the @dfn{selected window}. This is the window where the
cursor is (usually) displayed when Emacs is ready for a command. The
-selected window usually displays the current buffer, but this is not
-necessarily the case.
+selected window usually displays the current buffer (@pxref{Current
+Buffer}), but this is not necessarily the case.
Windows are grouped on the screen into frames; each window belongs to
one and only one frame. @xref{Frame Type}.