Also, Wikipedia says:
"A long black is a style of coffee, most commonly found in New Zealand and Australia, but now becoming available in the UK, predominantly in London. It is made by pulling a double-shot of espresso or ristretto over hot water (usually the water is also heated by the espresso machine). A long black is similar to an Americano, which is made by adding hot water to espresso shots, but it retains the crema and is less voluminous, therefore more strongly flavoured.
The order in which a long black is made (water first, espresso second) is important; reversing the steps will destroy the crema from the espresso shots.
Short black is an Australasian synonym for the basic espresso."