Grand Marnier Cordon Rouge is a classic orange curaçao liqueur made with cognac, bitter orange peel, and sugar. It is used in numerous cocktails, but it's often sipped neat or on the rocks (or even used in desserts, which is very popular in France. Unlike triple sec, curaçao is made with only bitter orange peel, rather than also using sweet orange peel.
Grand Marnier was invented by Alexandre Marnier-Lapostolle in 1880. The name "Cordon Rouge" means "red ribbon," referring to the signature packaging it has sported ever since.