Why does the East Coast get so many hurricanes, and the West Coast almost never does?

The East Coast gets hit because the Atlantic Ocean lies to its east, and the prevailing winds at that latitude come from the east. These two factors, combined with the warm sea water around the Tropic of Cancer provide the necessary conditions for cyclone development. On the West Coast of the U.S. the prevailing winds and current come down from the north where the water is considerably cooler--cold, in fact--which tends to keep storms from developing. Also, the winds are not as violent. Basically, the westward flow of the winds at the tropical latitudes carry any forming storms away from North America. The western side of Mexico does occasionally get hit by a hurricane, but no hurricane in recorded history has ever hit the west coast of the U.S.