Yes, she was first, but was never intended for true operational use. She was an experimental ship, converted from a collier. Intended to provide experience in operating a carrier.
Lexington and Saratoga were built on battle cruiser hulls. Ranger was the first carrier designed as such from the keel up. However, they tried to make a smaller cheaper carrier, (sound familiar?) and it never really worked out well.
First successful purpose built class was the Yorktown class, consisting of Yorktown, Enterprise and Hornet. Yorktown was sunk at Midway, Enterprise was damaged but survived the war. Hornet, from which the Doolittle raid was launched, was sunk late in the war, but it took 16 torpedoes, both US and Japanese, plus bombs and a Kamikaze, to do the job. (She was damaged at Santa Cruz, and had to be abandoned due to approach of Japanese forces. US tried to sink her, couldn't, Japanese tried to tow her, couldn't, and they finally sank her with torpedoes.)
Oops, not that late, meant to say later. The Battle of Santa Cruz Island took place 26 October 1942.