Almost every beer has a date printed on it. When treated properly, this is the date the brewery believes their beer still tastes as they intended it. There are a few ways to label this date. Other breweries use what is called a Julian date code printed on the neck of the bottle.
The first alphabet represents the month (e.g. 'A' for January). The two numbers after that represent the month's date (e.g. '08' for the 8th of January'). The following number after that represents the year (e.g. '4' for 2014). The next alphabet represents the shift when the beer was produced.