Water temperature
How hot the brewing water is, which affects how much flavour is extracted.
Most coffee brews well between about 90–96°C. Hotter water extracts faster and can taste harsh; cooler water can taste flat and sour.
Just-off-the-boil works for most methods; variable-temperature kettles give more control for light roasts and filter.
Why it matters for small spaces
Knowing the range means you rarely need a fancy kettle — a short rest after boiling is often enough.