— Command: emacs-version &optional here

This function returns a string describing the version of Emacs that is running. It is useful to include this string in bug reports.

          (emacs-version)
            ⇒ "GNU Emacs 23.1 (i686-pc-linux-gnu, GTK+ Version 2.14.4)
                       of 2009-06-01 on cyd.mit.edu"

If here is non-nil, it inserts the text in the buffer before point, and returns nil. When this function is called interactively, it prints the same information in the echo area, but giving a prefix argument makes here non-nil.

— Variable: emacs-build-time

The value of this variable indicates the time at which Emacs was built. It is a list of four integers, like the value of current-time (see Time of Day).

          emacs-build-time
               ⇒ (20614 63694 515336 438000)

— Variable: emacs-version

The value of this variable is the version of Emacs being run. It is a string such as "23.1.1". The last number in this string is not really part of the Emacs release version number; it is incremented each time Emacs is built in any given directory. A value with four numeric components, such as "22.0.91.1", indicates an unreleased test version.

— Variable: emacs-major-version

The major version number of Emacs, as an integer. For Emacs version 23.1, the value is 23.

— Variable: emacs-minor-version

The minor version number of Emacs, as an integer. For Emacs version 23.1, the value is 1.