* Buffer Type:: The basic object of editing.
* Marker Type:: A position in a buffer.
* Window Type:: Buffers are displayed in windows.
-* Frame Type:: Windows subdivide frames.
+* Frame Type:: Windows subdivide frames.
+* Terminal Type:: A terminal device displays frames.
* Window Configuration Type:: Recording the way a frame is subdivided.
* Frame Configuration Type:: Recording the status of all frames.
* Process Type:: A subprocess of Emacs running on the underlying OS.
@xref{Frames}, for a description of the functions that work on frames.
+@node Terminal Type
+@subsection Terminal Type
+@cindex terminal type
+
+ A @dfn{terminal} is a device capable of displaying one or more
+Emacs frames (@pxref{Frame Type}).
+
+ Terminals have no read syntax. They print in hash notation giving
+the terminal's ordinal number and its TTY device file name.
+
+@example
+@group
+(get-device-terminal nil)
+ @result{} #<terminal 1 on /dev/tty>
+@end group
+@end example
+
+@c FIXME: add an xref to where terminal-related primitives are described.
+
@node Window Configuration Type
@subsection Window Configuration Type
@cindex window layout in a frame