The words
Garde Manger literally means
"the guardian of meats", but this was in old
Europe.
Nowadays this chef de partie is in charge of the cold kitchen and anything that is prepared there. Although it will be for the most parts sandwiches and salads, the experienced garde manger will most probably also know how to make ice cream and desserts which usually is made by the patissier or someone who works under the patissier.
There also are dishes which contain both hot and cold ingredients served together, called chaud froid, the garde manger is also responsible for these dishes. Cold lettuce base with a warm chicken galantine is a common chaud froid dish that will come from the cold kitchen.
Plating and a good sense of aesthetics are very important in becoming a good garde manger, as the creations that come out of this particular section of the kitchen are mostly composed and must be nice to look at aside from being nice to the palate.