After the attack on Pearl Harbor the US had two Lexington class carriers (Lexington and Saratoga) and three Yorktown class carriers (Yorktown, Enterprise and Hornet) in operation in the Pacific. Lexington was lost in the Battle of the Coral Sea, Yorktown was lost during the Battle of Midway and Hornet was lost during the Battle of the Sante Cruz Islands. Saratoga and Enterprise survived the war with Enterprise being the most decorated U.S. aircraft carrier of WWII having participated in every Pacific battle.
These were followed by the U.S. most numerous aircraft carrier class of WWII, the Essex class (22 built). Each of the previous class carriers that were lost had an Essex class namesake.
While there were far more Essex class carriers, those first five Lexington and Yorktown class carriers literally won the war in the Pacific for the U.S. The Hornet, just back from the Doolittle raid, lost all 15 of her torpedo bombers (TBD's) and all but one of the pilots (VT-8) during the Battle of Midway but they were able to bring the fighter cap down allowing Enterprise and Yorktown SBD's to wreak devestation on the Japanese.
Not a single Essex class carrier was lost in the war.

to the brave men who fought and gave their lives in those early battles against the Japanese.