Hops are traditionally identified as bittering, aroma, or dual-purpose hops. These classifications indicate when hops are added during the boil, the brewing process after mashing and prior to fermentation. Bittering hops are added at the beginning of the boil; they provide the bitterness found in many beers, most notably IPAs and Pale Ales. Aroma hops are added during the final 20 minutes of the boil; they provide many different hop flavors and aromas to beers, such as the citrus, spicy, and herbal flavors found in IPAs. Dual-purpose hops are used for both. Bitterness levels are indicated as a measure of alpha acids contained in the hops, and each hop variety has its own set of flavor and aroma contributions.

Cascade: an aroma hop that provides citrus, grapefruit, floral, and spicy flavors. It is a mainstay of West Coast Pale Ales and IPAs, and is one of the original hops of craft beer, dating back to the 1970s.

Centennial: a dual-purpose hop that offers clean bitterness with floral and citrus flavors when used as an aroma hop. While not as citrusy as Cascade, it is sometimes referred to as “Super Cascade.” Mainly used in IPAs and Pale Ales.  

Chinook: a dual-purpose hop that features spicy and piney flavors with some underlying grapefruit. Works well as a bittering hop due to high alpha acid levels, but also a good choice for late additions. Standard in IPAs and Pale Ales, but also used in Stouts.

Columbus: high alpha acid hop traditionally used for bittering, but has recently found favor as an aroma hop. Provides clean bitterness and intense earthy, spicy, and citrus flavors. Appears in numerous styles, including IPAs, Pale Ales, Stouts, and Lagers.

Crystal: a versatile aroma hop that offers mild floral and spicy hop flavors; it is used in everything from Lagers to IPAs to Pilsners to Belgian Ales.

Fuggle: an aroma hop originally from England, but now grown in the U.S. Imparts earthy, woody, and fruity flavors, and is a mainstay of British style beers like ESBs and British IPAs, but also appears in American Pale Ales and IPAs.

Galena: a general-purpose high alpha bittering hop that is clean and well-balanced. Increasingly used as a aroma hop, providing citrus, spicy, and fruity hop flavors; works well in both English and American style beers.

Mt. Hood: an aroma hop that is usually mild, but at times can be pungent with spicy and herbal flavors. Has a clean, even bitterness. Works well in Lagers and Pilsners, and is a half-sister to Crystal.

Nugget: a high alpha dual-purpose hop that works equally well as a bittering or an aroma hop, imparting herbal flavors along with a slight spiciness. Used in a range of styles, including IPAs, Pale Ales, Stouts, and Saisons.  

Southern Cross: originally from New Zealand; a dual-purpose hop with soft bitterness and citrus, lemon zest, resin, and pine flavors when used as an aroma hop.

Williamette: an aroma hop that is mild and fragrant with floral, spicy, and citrus flavors accompanied by underlying herbal hints. Often featured in Pales Ales and English style ales, but also works well in Lagers.

Zeus: a high alpha bittering hop often referred to CTZ, which stands for Columbus, Tomahawk, and Zeus, although Zeus is genetically distinct. It provides earthy, citrus, and spicy hop flavors when used as an aroma hop.