The Large Magellanic Cloud is a nearby irregular galaxy and a satellite of the Milky way. It is the brightest visible galaxy from earth. It has a mass equivalent to approximately 10 billion times the mass of our Sun (1010 solar masses), making it roughly 1/100 as massive as the Milky Way.
It is visible as a faint “cloud” in the night sky of the southern hemisphere. It is unlike most galaxies which are visible only with the aid of a telescope.
Source: http://en.wikipedia.org/wiki/Large_Magellanic_Cloud