  Starting with Einstein's famous papers of 1905, we review some of the ensuing
developments and their impact on present-day physics. We attempt to cover
topics that are of interest to historians and philosophers of science as well
as to physicists. This paper will appear in ``2005: The Centenary of Einstein's
Annus Mirabilis'', the special March 2006 issue of Studies in History and
Philosophy of Modern Physics.
