An important part of studying long gamma-ray bursts (GRBs) lies in studying their environments. On the one hand, GRB host galaxies provide us with clues to better understand these extreme explosions. On the other hand, we can use GRBs to pinpoint faint star-forming galaxies and to trace star-formation accross the Universe. In the recent years a number of unbiased GRB samples have been compiled. Thanks to these samples, which are highly complete in redshift, we can finally understand the intrinsic properties of the GRB host galaxy population. In this review we give a brief summary of the main characteristics of GRB host galaxies and their relation to the field star-forming population. We mainly focus on the results we obtained by studying the complete BAT6 sample.