Glassware
The glass is part of the recipe, not the packaging.
The shapes that matter
Cocktail glass. The thin stem and triangular bowl are so tied to the idea of a cocktail that bars put the silhouette on their signage. Used for drinks served "up," the Martini above all.
Coupe. Increasingly the default for up drinks instead of the cocktail glass. The curves simply look more refined, and it's less prone to sloshing.
Collins & highball. Tall and narrow, and near enough interchangeable, though a Collins is the taller of the two. These are for drinks with ice and something carbonated.
Rocks. Also called an Old-Fashioned glass, holding six to ten ounces, for drinks served neat or over ice. A double is a couple of ounces larger.
Shot glass. No standard size exists, but most hold between one and a quarter and one and a half ounces, which makes them usable as a rough measure.
Flute & wineglass. A flute's narrow bowl and delicate stem preserve bubbles in anything sparkling, while a wineglass lends a bit of occasion to a drink that would otherwise look plain.