Snacks is a marketing expression that's gone into common usage meaning a small meal, as distinct from a major meal. It applies to packaged food in small servings like packets of corn chips, sweets, individually packed food servings, etc. In some cases the usage is derogatory, implying not enough food, or dismissive of the quality of the food provided. In other cases the use is sarcastic, referring to large amounts of food as inadequate.