Traditionally there are two styles of beer: ale and lager. Most types of beer will either fall into one category or the other.
Ale is brewed at a higher temperature than lager and uses yeast that sits at the top of the fermentation vessel. It ferments quickly and is characterized by a sweet, full bodied and fruity flavour. Many ales, such as India pale ales, contain more hops which results in a slightly bitter taste to help balance the sweetness. Types of beer in the ale category include pale ales, wheat beers, bitters, porters, stouts, barley wines, brown ales and tripels.
Lager is brewed at a lower temperature and uses bottom-fermenting yeast. It ferments slowly, usually over a period of at least three weeks, and is characterized by a “crisper” flavour than ale and has less hop flavouring. Types of beer in the lager category include pilsners, vienna lagers, bocks and marzens.
And now some (and certainly not all!) specific types of beer…
Altbier: A German ale with a copper-bronze appearance and a mildly fruity flavour with more hops than is usual in other German styles and a dry finish. Its alcohol content is medium.
Amber Ale: An ale without a precise definition. The name generally refers to pale ales which are more amber in colour (light copper to light brown). Usually a small amount of crystal or other coloured male is added to amber ales which gives them a bit darker colour than a typical pale ale. They have more malt flavour and less hoppiness than traditional pale ales. Its alcohol content is medium.
Barley Wine: A strong ale that ranges in appearance from amber to almost black. It is one of the strongest styles of beer (it gets its name for being as potent as wine) and has a very fruity, yet alcoholic, flavour. Sometimes this fruitiness is balanced out by hops. Its alcohol content is high.
Bitter: An English ale with a generally deep bronze appearance and a well-hopped flavour with greater depth than an IPA. Its alcohol content is medium to low (with the extra or special bitters being medium high to high). Bitters vary in strength, flavour and appearance and are often divided into the following sub-categories: session or ordinary bitter, best or regular bitter and premium or strong bitter (often called Extra Special Bitters (ESB)).
Bock: A German lager which ranges in appearance from light to amber and a malty, toasty flavour with a slightly sweet finish. Its alcohol content is high. Like bitters, bocks are divided into several sub-types: maibock or helles bock, doppelbock, and eisbock.
Brown Ale: An ale with a “brown” (hence the name) or amber appearance and a sweet, mild flavour. Its alcohol content is low to medium low. It is typically an English style of beer, although there are some Belgian brown ales.
Doppelbock: A stronger and darker version of Bock. Usually dark brown in appearance with a malty and bitter flavour. Its alcohol content is high.
India Pale Ale (IPA): An ale with a light amber appearance that is characterized by its citrus and hoppy, bitter flavour. Its alcohol content is medium to medium high.
Lambic Ale: A style unique to Belgium, lambics are a bit different than ales and lagers as they are spontaneously fermented (uses wild yeast by exposing the beer to open air to allow naturally occurring yeast and bacteria to “infect” the beer). It has a hazy appearance (as lambics are usually unfiltered), but may range in colour, and a dry and cidery flavour with a somewhat sour finish. Its alcohol content is medium.
Marzen: A German lager with a generally dark copper colour and a full-bodied, malty flavour with a clean, dry finish. Its alcohol content is medium strong. It is traditionally seasonal to Octoberfest (and also known as Oktoberfestbier).
Pale Ale: An ale that is bronze or copper coloured (not “pale” compared to pilsners but far lighter than the darker ales like stouts and porters). There are a broad range of pale ales but they all generally have a hoppy, dry flavour with some malt taste. Its alcohol content ranges from medium low to medium high.
Pilsner: A lager with a golden colour and crisp, dry and hoppy flavour (the hop flavour is distinct from all other types of lagers). Its alcohol content is medium. It is the most common type of beer brewed in North America (i.e. Budweiser, Kokanee, and Heineken are all pilsner-style beers)
Porter: A dark ale similar to stouts but lighter bodied and often without the roasted barley used in stouts. It usually has a complex flavour and often includes special flavours such as coffee, vanilla, or bourbon. Its alcohol content is medium.
Red Ale: An Irish ale with a reddish appearance and a lightly hopped and toasted malt flavour with a dry finish. It may also be slightly sweet. Its alcohol content is medium. There are also Belgian Reds (more sour notes) and American Red Ales (similar to amber ales).
Stout: An ale that has a dark brown to black appearance and is characterized by the use of roasted barley, which gives it a dry, roasted flavour with notes that vary from coffee to chocolate to slightly burnt. Its alcohol content is medium to medium high.
Tripel: A Belgian ale with a golden appearance (but darker than a pilsner) and a sweet flavour with a dry and spicy finish. Its alcohol content is high.
Vienna Lager: A German lager that has an medium dark amber or reddish appearance. It is rich bodied with toasty malt and caramel flavours and a sweet finish without much hops. Its alcohol content ranges from medium low to medium high.
Wheat Beer (or Hefeweizen): An ale with a light yet very hazy appearance. It has a special yeast that often gives the beer a slight banana or clove flavour. There may also be a bit of a spicy or apple taste and no hop bitterness. Its alcohol content is medium. Wheat beers are often served with a lemon wedge.