— 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 20.3.5 (i486-pc-linux-gnulibc1, X toolkit)
           of Sat Feb 14 1998 on psilocin.gnu.org"
     

If here is non-nil, it inserts the text in the buffer before point, and returns nil. Called interactively, the function 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 at the local site. It is a list of three integers, like the value of current-time (see Time of Day).

          emacs-build-time
               => (13623 62065 344633)
     

— Variable: emacs-version

The value of this variable is the version of Emacs being run. It is a string such as "20.3.1". The last number in this string is not really part of the Emacs release version number; it is incremented each time you build Emacs in any given directory. A value with four numeric components, such as "20.3.9.1", indicates an unreleased test version.

— Variable: emacs-major-version

The major version number of Emacs, as an integer. For Emacs version 20.3, the value is 20.

— Variable: emacs-minor-version

The minor version number of Emacs, as an integer. For Emacs version 20.3, the value is 3.