  We measure the static frictional resistance and the real area of contact
between two solid blocks subjected to a normal load. We show that following a
two-step change in the normal load the system exhibits nonmonotonic aging and
memory effects, two hallmarks of glassy dynamics. These dynamics are strongly
influenced by the discrete geometry of the frictional interface, characterized
by the attachment and detachment of unique microcontacts. The results are in
good agreement with a theoretical model we propose that incorporates this
geometry into the framework recently used to describe Kovacs-like relaxation in
glasses as well as thermal disordered systems. These results indicate that a
frictional interface is a glassy system and strengthen the notion that
nonmonotonic relaxation behavior is generic in such systems.
