Brewing requires three basic processes: mashing, boiling and fermenting. The first two, mashing and boiling, generally occur on the same day. Fermentation lasts for one to several weeks. Here's a brief description of each process.

Mashing: This process, which lasts from two to five hours, extracts fermentable sugar and other important compounds from the malt. First, the malt is coarsely ground, then mixed with warm water and allowed to sit at a temperature of about 150 °F (65 °C). After this, the sugar-rich water (now called wort, pronounced wert) is drained off and the malt is rinsed with fresh, hot water to extract as much sugar as possible.

Boiling: Wort from the mash is boiled in the kettle, usually for one to two hours. During the boil, hops are added at various times in order to impart the bitterness, flavor and aroma that the brewer desires. At the end of the boil, the wort is separated from the hops and chilled to prepare it for fermentation.

Fermentation: Yeast is added to the wort to initiate the fermentation that will convert it to beer. Ale fermentations take five to 10 days at temperatures of 60 to 70 °F (16 to 21 °C). Lagers generally take longer, with an initial fermentation at 50 to 55 °F (10 to 13 °C) followed by a period of cold storage or lagering at a temperature of about 35 °F (1 °C). At the end of fermentation, the beer is carbonated and then packaged for serving or delivery.