Buffers and Files

Some Basic Definitions

Buffer

A "hunk" of text in Emacs that can be edited. A buffer might be associated with a file, but does not need to be.

File

A "hunk" of text on secondary storage that persists between Emacs sessions. Buffers can be written to a file. Buffers may be associated with a file.

Buffers are the hunks of text that emacs edits. Some buffers are tied to files, so that changing a buffer will (eventually) change the file. But buffers may be generated on the fly for any purpose whatsoever, and need not be directly tied to the contents of a file. The separation of buffers and files allows some interesting modes of operation (e.g. dired mode).

The current buffer will display its name in the mode line.

    C-X b       Switch to a different buffer (prompted for name)
    C-X C-B     List all available buffers.
    C-X k       Delete a buffer (prompted for name)