An americano is an espresso lengthened with hot water — typically one double shot into 120 to 200 ml of water, in a mug.
Why it exists
The usual story is American soldiers in Italy during the Second World War finding espresso too intense and asking for it diluted. Whether or not that is literally true, the drink is what it sounds like: espresso adapted to a mug-sized habit.
Why it beats a lungo for most people
A lungo pushes more water through the coffee, which extracts further and picks up the bitter compounds that arrive late. An americano extracts a normal, well-balanced espresso and dilutes it afterwards.
The result keeps the character of the shot — the sweetness, the acidity, the origin notes — at a gentler concentration. It is a cleaner drink, and it is much easier to make well.
The order matters
Pour the hot water first, then the espresso into it. This preserves the crema as a layer on top rather than breaking it up, and it means the shot is not sitting in a cold cup losing heat while you deal with the kettle.
Long black
The Australian and New Zealand version uses less water — around 100 to 120 ml — so the drink is stronger and the crema more prominent. If you find americanos watery, order or make a long black instead.
Getting it right at home
Use water just off the boil rather than boiling, at roughly 1:3 or 1:4 espresso to water. Start there and adjust to taste — this is a drink with no wrong answer.
Questions people actually ask
Should the water go in first or the espresso?
Water first. Pouring espresso into water preserves the crema on top; pouring water onto espresso breaks it up. It also stops the shot sitting in a cold cup while you fill the kettle.
Is a long black the same thing?
Nearly. A long black is espresso poured over hot water in a smaller volume, and it is the Australasian version. The distinction most people notice is that a long black keeps more crema and more intensity.