Nano brewery, craft brewery, microbrewery: how can you keep them all straight. For the average beer consumer, the distinction between these "types" of breweries doesn't matter much; as long as they make good beer, right?! But let's try to get all these terms straight.
What's in a name? That which we call a brew by any other name would taste as sweet.
The largest term is craft brewery. A craft brewery puts out annually less than 6 million barrels of beer a year. Less than 25% of the brewery is owned by an "alcoholic beverage industry member": meaning it's independently owned. The beers produced are innovative and mostly malt-based. The term craft brewery is used to distinguish itself from a macro-brewery, like Coors (over 20 million barrels per year). Sierra Nevada brews 780,000 barrels annually.
A microbrewery is a craft brewery with lower output, producing less than 15,000 barrels a year. With trends moving to local beers, some say the bar should instead be at producing less than 50,000 barrels a year. Ninkasi Brewing Company, for example produced 32,000 barrels last year but is considered a microbrewery by most. Smuttynose Brewing Co is New Hampshire produced 20,000 barrels last year. Allagash Brewing Co in Portland, ME produces 4,000 barrels a year. Microbreweries are usually community-oriented and not largely distributed.
A brewpub is a pub or restaurant that brews on-site. Pizza Port Brewing Co in California is a brewpub.
A nano-brewery has less than a 4 barrel brew system. They are also referred to as large-scale homebrewers. Most micro and craft breweries started as nano-breweries; some stay small with no desire to grow. Ambacht Brewing Co in Hillsboro, OR and Hess Brewing Co in San Diego, CA are both nano-breweries.