“Sarge and the Buck­et ‘O’ Sol­diers are set in par­tic­u­lar posi­tions. They are high­ly dis­ci­plined with a “leave no man behind” pol­i­cy and are mas­ters of recon­nais­sance. Woody describes them as “pro­fes­sion­als.” Sarge and his sol­diers go on mis­sions to help Andy’s toys check up on Andy’s activ­i­ties with his friends or fam­i­ly. Sarge and his troops fre­quent­ly help out their fel­low toys.”

Source: http://disney.wikia.com/wiki/Sarge_(Toy_Story)