Cold brew, or cold water extract, refers to the process of preparing coffee in water at room temperature or cold water. Cold brew coffee is not to be confused with iced coffee, which refers to coffee that is brewed hot and then chilled by pouring over, or adding ice.
There are various ways to prepare cold brew coffee. The most common brewing methods are immersion cold brew, (steeping), and cold drip, (Dutch coffee). There are also emulsion cold brew, vacuum cold brew, pressure cold brew, and hot bloom cold brew.
The most used two methods are immersion cold brew and drip cold brew. In general, cold brew requires 6 or more hours of steeping or dripping. A special case is vacuum brewing which only need minutes to complete a full extraction cycle.
Cold brew is typically inexpensive, regarding the equipment used, though exceptions exist. The cheapest cold brew coffee maker is a simple food recipient, where coffee is steeped for 12 or more hours. Commercially available cold brew makers are designed to brew large quantities, in order to compensate for the brewing time.