I have no idea how or when the Frappé became a staple of Greek lifestyle and cuisine, but here it is, in all its ubiquitous splendour.
Wherever you go in Greece, prepare to see people in the bars sipping their frappé in a glass or walking in the street clutching to a transparent plastic cup with a thick frother layer at the top from which emerges a straw :
Usually, you are asked how much sugar you want in it γλυκός, μέτριος, σκέτος) and if you want milk (με γάλα) added.
So if you like your frappé with medium sugar, say:
ένα φραπέ μέτριος με γάλα
(ena frappé metrios me gala)
And it's true it's good in summer.