ESB, or Extra Special Bitter is a classic English style. It is bitter, hence the name, but not that bitter by today's standards. Usually between 30-40 IBU, it is actually quite balanced with malt flavor, and makes for a nice well-rounded ale, no fancy bells and whistles but just a straight up hoppy ale. They are actually pretty refreshing once in awhile when taking a break to the super high IBU (70-100 IBU) beers and highly dry-hopped pale ales.