Asteroid 2013 YC14 passed the Earth at a distance of 4 413 000 km (slightly under 11.5 time the distance between the Earth and the Moon) a little after 3.35 pm GMT on Tuesday 26 December (Boxing Day) 2013. There was no danger of the asteroid hitting us, and had it done so it would have presented only a minor risk. 2013 YC13 is thought to be between 23 and 71 m in diameter, and an object of this size would be expected to break up in the atmosphere between 22 and 3 km above the Earth's surface, with only fragmentary material reaching the ground, although being directly in the path of an object towards the upper end of this range would probably be fairly unpleasant.
The calculated orbit of 2013 YC14. JPL Small Body Database Browser.
2013 YC14 was discovered on 26 December 2013 (Boxing Day, the day of its closest pass to the Earth) by the University of Arizona's Catalina Sky Survey in the Catalina Mountains north of Tucson. The designation 2013 YC14 implies that it was the 351st asteroid discovered in the second half of December 2013 (period 2013 Y).
While 2013 YC14 occasionally comes near to the Earth, it does not actually cross our orbital path. It has an elliptical 539 day orbit, tilted to the plane of the Solar System, that takes it from 1.004 AU from the Sun (1.004 times the distance at which the Earth orbits the Sun), slightly outside our orbit, to 1.59 AU from the Sun, (1.59 times the distance at which the Earth orbits the sun and slightly outside the orbit of the planet Mars), so unless an encounter with another body causes it's orbital path to alter in a very specific way (highly unlikely) there is no chance of it hitting the Earth. As a Near Earth Object that remains strictly outside the orbit of the Earth it is classed as an Amor Family Asteroid.
See also Asteroid 2013 WD44 Passes the Earth, Asteroid 2013 XA4 passes the Earth, Asteroid 2013 XY20 passes the Earth, Asteroid 2013 XW8 passes the Earth and Asteroid 2013 UC1 passes the Earth.
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