What does "small beer" mean?

Also, small potatoes. Of little importance, as in Don't listen to Henry; he's small beer, or It's silly to worry about that bill; it's small potatoes. The first term alludes to a beer of low alcoholic content (also called light beer today) and was used metaphorically by Shakespeare in several plays. The variant may have been invented by frontiersman Davy Crockett; it was first recorded in 1836. Also see small fry, def. 2.