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**Galactic** clusters like *Pleiades* and *Hyadam* and **globular** clusters are *similar* in the following respects:
 **a**) They consist of stars of different spectral classes.
 **b**) They are gravitational systems, as obvious and certain as binary stars, although the periods of revolution or oscillation of stars relative to the gravitational centers of clusters are immeasurably long.
 **c**) Their distribution across the sky indicates their belonging to the galactic system.
 **d**) In almost every galaxy cluster, the brighter stars are indeed brighter: they are giants compared to the Sun, and often supergiants.
 **Differences** are more significant than similarities:
 **a**) Galaxy clusters are closely related to the Milky Way:
 all of them, with the exception of two or three, are from the galactic plane at distances not exceeding three thousand light-years;  globular clusters known to us are found in all galactic latitudes, they are more numerous near the borders of the Milky Way, but there is not a single cluster located
 closer than two thousand years from the galactic plane.