Infusion is a process of extracting flavors or nutrients from a substance by steeping it in a liquid. This is commonly done with spices, herbs, tea, and coffee. To make an infusion, the substance is added to a container with hot liquid, covered, and left to steep for a period of time. The liquid is then strained to remove the solids and the resulting infusion is used in cooking or consumed as a beverage. Infusions can be made with water, milk, or other liquids and can be served hot or cold.