  Following the observation and analysis of large-scale coronal wave-like
disturbances, we discuss the theoretical progress made in the field of global
coronal seismology. Using simple mathematical techniques we determine average
values for magnetic field together with a magnetic map of the quiet Sun. The
interaction between global coronal waves and coronal loops allows us to study
loop oscillations in a much wider context, i.e. we connect global and local
coronal oscillations.
