Process shapes the fruit in the cup.
Washed coffees taste clean and bright; naturals, fruitier and heavier — and easier to muddle.
What it is
What happens to the coffee cherry after picking. Washed coffees have the fruit removed before drying; naturals dry inside the whole fruit; honey sits in between.
Why it matters
Washed coffees tend to taste clean and bright. Naturals are fruitier and heavier, and turn muddled when over-extracted, so a slightly cooler brew keeps them clean.
In practice
The process is usually printed on the bag. If it isn't, choose "Don't know": the app keeps the recipe's defaults.