Ale is a broad category which includes numerous types and styles of which it can be somewhat arbitrary and not necessarily helpful to distinguish, needless to say though Stouts and Porters are given a seperate section on this website they too are types of ale, as are many of the Belgian beers on this site. Here are some comments.
ALE:
Generally speaking Ale is brewed using top fermenting yeasts which is contrasted to Lagers which are bottom fermenting. (However, this top/bottom distinction is not absolute as there are in-betweens). Ales tend to be brewed at warmer temperatures than Lagers meaning that they ferment more quickly. As a result of the brewing process Ales tend to have a smoother texture and richer fruitier flavour.
REAL ALE:
Today most ales aren't real ales. The term Real Ale was coined by CAMRA in the 1970's; it refers to Ales that are neither Pasteurised nor Filtered and contains no artificially added Carbon Dioxide.
Filtering and pasteurisation kills the yeast which ferments the sugars during brewing. By not destroying the yeast the beer remains 'alive' and as such can mature by undergoing 'secondary fermentation' in either the cask or bottle in which it is distributed - "cask conditioned" or "bottle conditioned" are terms used to indicate this.
Carbon Dioxide is produced naturally during fermentation. Fuck knows why anyone would want to add more - it only makes you burp. This is primarily a characteristic of cheap and nasty Lagers which taste disgusting and as such are served cold and made fizzy to numb the tastebuds and prevent the drinker tasting the true flavour of the beer.
Some brewers add nitrogen: many "draught" beers, beers with the names like Smoothflow or Creamflow and canned beers with widgets are known as nitro-keg and have added nitrogen (which is where Guinness Draught gets its famous white head). Nitrogen creates smaller bubbles which makes for a smoother kind of fizz.
TYPES OF ALE:
there are many. Here are a few:
Bitter:
Bitter is a term used by a lot of people to describe pretty much everything between Lager and Stout. This is wrong. Ales tend to be a combination of sweet/rich malts and bitter hops flavours. A Bitter is ale brewed with a greater concentration of hops so that the bitterness of the hops comes to dominate the flavour. the bitterness of the ale is also dependent upon what stage of the brewing process the hops are added to beer - the earlier the hops are added the more hop flavour there will be in the final product. In this case the character of the ale is determined largely (but by no means entirely) by the variety and strength of the hops used.
To be honest I'm not a big fan of Bitter, I prefer a more well balanced ale.
Mild:
A mild can be dark or pale. It is ale without the excessive hops and bitterness of Bitter - on the whole is a more malty or well-balanced ale.
Pale Ale:
An ancestor of bitters, light in colour.
India Pale Ale was brewed stronger and with more hops (which are natural preservatives) to ensure that the beer shipped from Britain survived the long time at sea and reached the colonies in drinkable condition.
Golden/Blonde Ale:
Fairly recent innovation. It seems ale producers producers wanted to create a refreshing light beer that would be suited for summer drinking and challenge Lagers dominance. Usually distinctive from Lager because of the strong hops used.
Old Ale:
Ale that has been matured for a considerable period of time. often rich in flavour and also often strong.
Porter:
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Stout:
I believe the term was originally used to signify strengh rather than simply to name a particular style. Its association with a certain style comes from the popularity of porters in the 18th and a tendency to brew them strong. Stout is now synonymous with Porter and the name is often used to classify darker and/or stronger varieties though this is by no means an established rule.
There are numerous varieties of stout...
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