
Boiling water is plain water heated to its boiling point — about 212°F / 100°C at sea level.
It heats the drink, dissolves honey and sugar that cold water leaves sitting, and makes up the volume. Water straight off the boil is right for melting honey and sugar. Let it stand a moment before it meets a delicate spirit: too hot, and the alcohol vapor burns the nose before you smell anything. Warm the glass first with a throwaway pour, or a cold glass steals much of the heat.
Water boils at a lower temperature at altitude, so tea and spices need noticeably longer to steep.
Freshly boiled drinking water
Pour it from a kettle, pan or microwave while it is still very hot.
Hot water
Tops up a drink fine. It is just served cooler, and honey or sugar takes noticeably longer to dissolve.
Boil fresh water each time as a habit. Reboiling is often blamed for flat-tasting water, but a test-kitchen tasting found no difference in tea made with twice-boiled water.