Craft beer or micro beer simply put.

Craft beer or micro brew or micro beer is beer not brewed by one of the "mega brewery" corporations. More often than not, when the phrase craft beer, craft brew, or micro brew is used, this is what it means. However, it is a rather imprecise thing to define by what it is not so lets take it a bit further. 

The brewer association in boulder, co. Defines craft or micro brew as beer made by a brewer that is small, independent, and traditional. This sums it up rather nicely and creates for the association a way to talk about what they are talking about.  However, there is some very good craft beer that should be called micro beer or micro brew beer. So, it should be pointed out that just because beer is called craft beer it should really be defined as micro brew or micro beer.

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