Captain Ginyu (ギニュー), also called Commander Ginyu, is the leading member of an elite mercenary platoon, the eponymous Ginyu Force. His name is a pun on gyunyu, the Japanese word for milk.
Captain Ginyu is shown to be very loyal to his men and to Frieza, and follows any order Frieza gives him. However, he also can be quite harsh to his team members if they fail a mission, as shown when he harshly scolded Jeice for letting Burter and Recoome lose to Goku, and escaping from the fight. His loyalty to Frieza appears to be so extreme that even after he has swapped bodies with a Namekian Frog, he tries to sneak a Namekian Dragon Ball away from Gohan to make sure that they do not use the Dragon Balls before Frieza can (or it may simply have been as revenge for such a humiliating defeat). However, despite his flaws, Ginyu has displayed a strong sense of honor in combat and prefers fairness in his battles, as shown when he refused to break Goku's neck due to Jeice interfering in their fight, and even threatening to kill Jeice if he did it again. Goku takes note of this and insinuates that Ginyu may not be all bad and even capable of redemption.
Like the other members of the Ginyu Force, Ginyu's special powers originated during his childhood. When Ginyu first learned of his Body Change ability, he swapped bodies with the richest kid in his class, which made him popular with girls but also stupid, and he soon realized that men should compete in terms of strength rather than money. Only a few people have seen Ginyu's true form, and Salza is among them. Salza had to fight Ginyu to become leader of Cooler's Armored Squadron.