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Buffer Type

A buffer is an object that holds text that can be edited (see section Buffers). Most buffers hold the contents of a disk file (see section Files) so they can be edited, but some are used for other purposes. Most buffers are also meant to be seen by the user, and therefore displayed, at some time, in a window (see section Windows). But a buffer need not be displayed in a window.

The contents of a buffer are much like a string, but buffers are not used like strings in Emacs Lisp, and the available operations are different. For example, text can be inserted into a buffer very quickly, while "inserting" text into a string is accomplished by concatenation and the result is an entirely new string object.

Each buffer has a designated position called point (see section Positions). And one buffer is the current buffer. Most editing commands act on the contents of the current buffer in the neighborhood of point. Many other functions manipulate or test the characters in the current buffer and much of this manual is devoted to describing these functions (see section Text).

Several other data structures are associated with each buffer:

The local keymap and variable list contain entries which individually override global bindings or values. These are used to customize the behavior of programs in different buffers, without actually changing the programs.

Buffers have no read syntax. They print in hash notation with the buffer name.

(current-buffer)
     => #<buffer objects.texi>

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