I wonder what the pressure difference is?
If espresso is by definition pressure-brewed coffee, is French press coffee a form of espresso?
A French press for coffee is known in the UK, sometimes, as a "cafeteria" and thought to be the source of the name now used for the restaurant style. However, wikipedia suggests the restaurant got its name another way.– Rincewind42Jul 12, 2011 at 0:31
Espresso is brewed by passing high pressure water through the coffee at a temperature lower than 100°C (i.e. not boiling water).
Guidelines from the Istituto Nazionale Espresso Italiano state that the entry water pressure is 9 ± 1 bar and the entry water temperature is 88 ± 2°C (67 ± 3°C in the cup). The coffe is brewed for 25 ± 2.5 s.
French press coffee, instead, is brewed by leaving the coffee for 2-4 minutes at atmospheric pressure (no high pressure involved) in 90-95°C water. The press in the name has nothing to do with high pressure, is just describing the fact that you press down the coffee grounds with the piston once it is brewed.
2If you're looking to categorize different brewing methods, French press is considered full immersion brewing.– mthorpJul 12, 2011 at 15:53