CAMRA is the Campaign For Real Ale. It is a consumer group with the main aim of promoting Real Ale and the traditional English pub.
What is "real ale"?
The fundamental distinction between real ale and other ales is that real ale is alive when you drink it, meaning unpasteurized. Because the yeast is still alive, the process of fermentation continues in the cask or bottle on the way to the consumer. This seconary fermentation allows for the development of greater complexity in the taste.