  Russell (1948) famously described eclipses as the "royal road" to stellar
astrophysics. From photometric and spectroscopic observations it is possible to
measure the masses and radii (to 1% or better!), and thus surface gravities and
mean densities, of stars in eclipsing binary systems using nothing more than
geometry. Adding an effective temperature subsequently yields luminosity and
then distance (or vice versa) to high precision. This wealth of directly
measurable quantities makes eclipsing binaries the primary source of empirical
information on the properties of stars, and therefore a cornerstone of stellar
astrophysics. In this review paper I summarise the current standing of
eclipsing binary research, present an overview of useful analysis techniques,
and conclude with a glance to the future.
