GeTe is a rather unconventional and complex compound from a fundamental point of view considering its very simple stoichiometry. Within this review, we first discuss the crystal structure of GeTe, focusing our attention on the bonding mechanism and on the distortion of the unit cell. This distortion is responsible for the ferroelectric properties of GeTe that are also considered here. Furthermore, we describe the amorphous phase and review the phase change material properties resorting to examples from several GeTe based alloys. Finally we examine the usage of GeTe for spintronics, a fairly recent application field.